Tag Archives: Wear OS

15 Things to know for Android developers at Google I/O

Posted by Matthew McCullough, Vice President, Product Management, Android Developer

AI is unlocking experiences that were not even possible a few years ago, and we’ve been hard at work reimaging Android with AI at the core, to help enable you to build a whole new class of apps. At this year’s Google I/O, we’re covering how new tools like Gemini can power building the next generations of apps on Android. Plus, we showcased a range of updates to our tools and services grounded in productivity, helping you make it faster and easier to build excellent experiences across form factors. Let’s dive in!

Powering the next generation of Apps with AI

#1: AI in your tools, with Gemini in Android Studio

Gemini in Android Studio (formerly Studio Bot) is your coding companion for Android development, and thanks to your feedback since its preview at last year’s Google I/O, we’ve evolved our models, expanded to over 200 countries and territories, and brought it into the Gemini family of products. Earlier today, we previewed a number of new features coming soon, like Code suggestions, App Quality Insights that leverage Gemini, and a preview of the multi-modal inputs that are coming using Gemini 1.5 Pro. You can read more about the updates here, and make sure to check out What’s new in Android development tools.

#2: Building with Generative AI

Android provides the solution you need to build Generative AI apps. You can use our most capable models over the Cloud with the Gemini API in Google AI or Vertex AI for Firebase directly in your Android apps. For on-device, Gemini Nano is our most efficient model. We’re working closely with a few early adopters such as Patreon, Grammarly, and Adobe to ensure we’re creating the best APIs that unlock the most innovative experiences. For example, Adobe is experimenting with Gemini Nano to enhance the on-device experience of Acrobat AI Assistant, a tool that allows their users to summarize and interact with documents. Be sure to check out the Build your own generative AI powered Android app, Android on-device gen AI under the hood, and the What’s New in Android sessions to learn more!

Moving image of Gemini Nano operating in Adobe

Excellent apps, across devices

#3: Think adaptive: apps on phones, foldables, tablets and more

Build and design apps that adapt beyond the phone, with the new Compose adaptive layout libraries built with Material guidance in beta. Add rich stylus and keyboard support to increase user productivity. Check out three of our key Android adaptive sessions at Google I/O: Designing adaptive apps, Building adaptive Android apps, and Increase user productivity with large screens and accessories.

#4: Enhance homescreens with Widgets and Jetpack Glance

Jetpack Glance 1.1 is now available in release candidate and lets you build high quality widgets using your Compose skills. Check out our new canonical layouts, design guidance and figma updates to the Android UI kit. To learn more check out our Improve the user experience of your Android app workshop and Build Android widgets with Jetpack Glance technical session.

#5-9: come back here tomorrow and Thursday!

We’ll continue to share more updates for Android Developers throughout Google I/O, so check back here tomorrow!

Developer Productivity

#10: Use Kotlin Multiplatform for sharing business logic

Kotlin Multiplatform (KMP) enables sharing Kotlin code across different platforms and several of our Jetpack libraries, like DataStore and Room, have already been migrated to take advantage of KMP. We use Kotlin Multiplatform within Google and recommend using KMP for sharing business logic between platforms. Learn more about it here.

#11: Compose: Shared Elements, performance improvements and more

The upcoming Compose June ‘24 release is packed with the features you’ve been asking for! Shared element transitions, lazy list item reordering animations, strong skipping mode, performance improvements, a new lazy flow layout and more. Read more about it in our blog.

#12: Android Studio: the latest preview, with Gemini and more

Android Studio Koala 🐨Feature Drop (2024.1.2) available today in the canary channel, builds on top of IntelliJ 2024.1 and adds new innovative features unlocked by Gemini, such as insights for crashes in App Quality Insights, code transformations and a Gemini API starter template to get you quickly started with Gemini. Additionally, new features such as USB speed detection, shortcut UI to control device settings, a new way to sign into Google services, updated and speedier UI for profilers with a new task centric approach and a deep integration with the Google Play SDK index are intended to make the development process extremely productive. Read more here.

And the latest from the world of Mobile

#13: Grow your business with the latest Google Play updates

Discover new ways to attract and engage users with enhanced custom store listings. Optimize revenue with expanded payment options. Reinforce trust through secure, high-quality experiences made easier with our latest SDK Console improvements. Learn about these updates and more, including our new vertical approach, in our blog.

#14: Simplify app compliance with Checks

Streamline your app's privacy compliance with Checks, Google's AI-powered compliance solution! Checks empowers developers to swiftly identify, address, resolve privacy issues, and enables you to launch apps faster and with confidence. Harness the power of automation with Checks' intelligent reports, saving you valuable time and resources. Get started now at checks.google.com.

#15: And of course, Android 15

…but for that, you’ll have to stay tuned tomorrow, when we’ve got a bit more up our sleeve!

Source: Android Developers Blog

Google I/O 2024: What’s new in Android Development Tools

Posted by Mayank Jain – Product Manager, Android Studio

At Google I/O 2024, we announced an exciting new set of features and tools aimed at making Android development faster and easier. We also shared updates to Android Studio that will help you leverage AI and make it easier for you to build high quality apps for Android across the Android ecosystem.

You can check out the What’s new in Android Developer Tools session at Google I/O 2024 to see some of the new features in action or better yet, try them out yourself by downloading Android Studio Koala 🐨 Feature Drop in the preview release channel. Here’s a look at our announcements:

Leverage Gemini in Android Studio

Since launching AI features in Android Studio last year, we continue to evolve our underlying models, integrate your feedback, and expand availability to more countries and territories so that you can leverage AI in your workflow and become a more productive Android app developer. Using the built-in AI privacy controls, you can opt in to using the latest AI feature improvements that are tailored for your Android app project.

Code suggestions with Gemini in Android Studio

You can now provide custom prompts for Gemini in Android Studio to generate code suggestions. After you enable Gemini from the View > Tool Windows > Gemini tool window, right-click in the code editor and select Gemini > Transform selected code from the context menu to see the prompt field. You can then prompt Gemini to generate a code suggestion that either adds new code or transforms selected code. You can ask Gemini to simplify complex code by rewriting it, perform very specific code transformations such as “make this code idiomatic,” or generate new functions you describe. Android Studio then shows you Gemini’s code suggestion as a code diff, so that you can review and accept only the suggestions you want.

Code suggestions with Gemini in Android Studio

Gemini for recommendations on crash reports

App Quality Insights in Android Studio seamlessly incorporates both Firebase Crashlytics and Android Vitals data into Android Studio so you can access the most important app stability related information, without having to switch tools.

You can now use Gemini in Android Studio to analyze your crash reports, generate insights which are shown in the Gemini tool window, provide a crash summary, and when possible recommend next steps, including sample code and links to relevant documentation.

You can generate all of this information directly from the App Quality Insights tool window in Android Studio after you enable Gemini from View > Tool Windows > Gemini.

Gemini for recommendations on crash reports

Integrate Gemini API into your app with a starter template

Start prototyping with Gemini models in your apps with our new starter app template provided in Android Studio. In this app template, you can issue prompts directly to the Gemini API, add image sources as input, and display the responses on the screen. Additionally, use Google AI Studio to craft custom prompts for your app.

When you are ready to scale your AI features to production with Google Cloud infrastructure, you can also access the powerful capabilities of Gemini models through Vertex AI. This is Google’s fully-managed development platform designed for building and deploying generative AI. Whether you simply need world class inference capabilities, or want to build end-to-end AI workflows with Vertex, the Gemini API is a great solution.

Integrate Gemini API into your app with a starter template

Gemini 1.5 Pro coming to Android Studio

We previously announced that Gemini in Android Studio uses the Gemini 1.0 Pro model to help you by answering Android development questions, generating code, finding resources, or explaining best practices. In this preview stage of Gemini in Android Studio, we are offering Gemini 1.0 Pro at no-cost for all users for now. Gemini 1.0 Pro is a versatile model, making it ideal to scale. However we acknowledge that its quality of responses may be limited in some cases. Based on your feedback, we are committed to improving the quality for Android development, and excited to add more features using Gemini to make your developer experience even more productive.

Along this journey, the Gemini 1.5 Pro model will be coming to Android Studio later this year. Equipped with a Large Context Window, this model notably leads to higher quality responses, and unlocks use cases like multimodal input that you might have seen in the Google I/O 2024 sessions. Stay tuned for more updates on how you can access more capable models in Android Studio.

Productivity enhancements

Release Monitoring with Firebase

Today we announced the general availability of the Firebase Release Monitoring Dashboard. The Firebase Release Monitoring Dashboard is a single dashboard powered by Firebase Crashlytics to monitor your most recent production releases of your Android app. It updates in real time to give you a high-level view of the most important release metrics, like crash-free sessions, comparisons, and benchmarking based on your previous releases.

Android Device Streaming

Android Device Streaming, powered by Firebase, lets you securely connect to remote physical Android devices hosted in Google's data centers. It is a convenient way to test your app against physical units of some of the latest Android devices, including the Google Pixel 8 and 8 Pro, Pixel Fold, and more.

Starting today, Android Device Streaming now includes the following devices, in addition to the portfolio of 20+ device models already available:

Samsung Galaxy Fold5
Samsung Galaxy S23 Ultra
Google Pixel 8a

Additionally, if you’re new to Firebase, Android Studio automatically creates and sets up a no-cost Firebase project for you when you sign in to Koala Feature Drop to use Device Streaming. So, you can get to streaming the device you need much faster. Learn more about Android Device Streaming quotas, including promotional quota for the Firebase Blaze plan projects available for a limited time.

Connect to the latest physical Android devices in moments with Android Device Streaming,
powered by Firebase

USB cable speed detection

Did you know that USB cable bandwidth varies from 480 Mbps (USB-2) to up to 40,000 Mbps (USB-4)? Android Studio Koala Feature Drop now makes it trivial to differentiate low performing USB cables from the high performing ones.

When you connect an Android device, Android Studio automatically detects the device and USB cable bandwidth and warns you if there’s a mismatch in USB bandwidth.

Note: USB cable speed detection requires an updated ADB found in Android SDK Platform Tools v34+, and is currently available for macOS and Linux.

USB cable speed detection.
Learn more about USB speeds here

A new way to sign in with Google in Android Studio

It’s now easier to sign in to multiple Google services with one authentication step. Whether you want to use Gemini in Android Studio, Firebase for Android Device Streaming, Google Play for Android Vitals reports, or all these useful services, the new sign in flow makes it easier to get up and running. If you’re new to Firebase and want to use Android Device Streaming, Android Studio automatically creates a project for you, so you can quickly start streaming a real physical Firebase device. With granular permissions scoping, you will always be in control of which services have access to your account. To get started, just click the profile avatar and sign in with your developer account.

A new way to sign in with Google in Android Studio

Device UI setting shortcut

Using the device UI setting shortcut, you can now effortlessly configure your devices to desired settings related to dark theme, font size, display size, app language, and more, all directly through the Running Devices window. You can now test and debug your UI seamlessly for any of the possible scenarios required by your use case.

Device UI settings shortcuts

Faster and improved Profiler with a task-centric approach

The internals of the Android Studio Profiler have been dramatically improved. Popular profiling tasks like capturing a system trace with profileable apps now start up to 60% faster.*

We’ve redesigned the profiler to make it easier to start the task you’re interested in, whether it’s profiling your app’s CPU, memory, or power usage. For example, initiating a system trace task to profile and improve your app’s startup time is integrated right in the UI as you open the profiler.

Faster and improved Profiler with a task-centric approach
*Based on internal data, as tested in April 2024

Google Play SDK Index integration

Android Studio is integrated with the Google Play SDK Index to inform when there are known policy or version issues with SDKs used by your app. This enables you to update those dependencies and avoid issues that could prevent you from publishing new versions of your app.

In the Android Studio Koala Feature Drop release, the integration has been expanded to also include warnings from the Google Play SDK Console. This gives you a complete view of any potential version or policy issues in your dependencies before submitting your app to the Google Play Console.

Notes from SDK authors are now also displayed directly in Android Studio to save you time.

A warning from the SDK Index with the corresponding SDK author note

Preview tiles for Wear OS apps

Android Studio now has preview support for Tiles. You can now iterate much quicker when creating tiles, enabling you to quickly see what a Tile looks like on different configurations without needing to run it on a device.

Tiles previews usage for Wear OS apps

Generate synthetic sensor data for testing on Wear OS apps

To help simulate real life scenarios you can now generate synthetic (fake) data for a Wear OS emulator for health related sensors such as heart rate, speed, steps, and more. You are now able to set up and perform testing for a multi-sport training session in minutes, end-to-end in Android Studio, without ever leaving your desk.

Generate synthetic sensor data for testing on Wear OS apps

Compose Glance widget previews

Android Studio Koala Feature Drop makes it easy to preview your Jetpack Compose Glance widgets (1.1.0-rc01) directly within the IDE. Catch potential UI issues and fine-tune your widget's appearance early in the development process. Learn more about how to get started.

Previews for Compose Glance widgets

Live Edit for Compose enabled by default

Live Edit for Compose can accelerate your Compose development experience by automatically deploying code changes to the running application on an emulator or physical device. Live Edit can help you see the effect of updates to UX elements—for example new composables, modifier updates, and animations—on the overall app experience. As you become more familiar with Live Edit you will find many creative ways it can help improve your development experience and productivity.

In Android Studio Koala Feature Drop, Live Edit is enabled by default in manual mode and has increased stability and more robust change detection, including support for import statements.

Compose Preview Screenshot Testing with Now in Android app

Compose preview screenshot testing plugin (alpha)

Host-side screenshot testing is an easy and powerful way to test UIs and prevent regressions. Today, the first alpha version of the Compose Preview Screenshot Testing plugin is available as a separate plugin, to be used together with AGP 8.5.0-beta01 or higher. Add your Compose Previews to the src/main/screenshotTest folder and run the task to generate a diff report after UI updates. The generated HTML test report lets you visually detect any changes to your app’s UI.

This alpha version of the plugin is designed for rapid iteration and feedback. We plan to merge it back into AGP in the future, but for now, this separate plugin lets us experiment and improve the feature quickly. Learn more about how to get started.

IntelliJ Platform Update (2024.1)

Android Studio Koala Feature Drop includes the IntelliJ 2024.1 platform release, which comes with some very useful IDE improvements:

An overhauled terminal featuring both visual and functional enhancements to streamline command-line tasks. Learn more in this blog post.
A new feature called sticky lines in the editor simplifies working with large files and exploring new codebases. This feature keeps key structural elements, like the beginnings of classes or methods, pinned to the top of the editor as you scroll and provides an option to promptly navigate through the code by clicking on a pinned line.
Basic IDE functionalities like code highlighting and completion now work for Java and Kotlin during project indexing, which should enhance your startup experience.
You can now scale the IDE down to 90%, 80%, or 70%, giving you the flexibility to adjust the size of IDE elements both upward and downward.

Read the detailed IntelliJ release notes here.

To summarize

Android Studio Koala Feature Drop (2024.1.2) is now available in the Android Studio canary channel with

Gemini in Android Studio

Productivity enhancements

IntelliJ Platform Update (2024.1): also available in Koala 2024.1.1

And last, a quick reminder that going forward, the initial Android Studio releases will have the .1 Android Studio major version and introduce the updated IntelliJ platform version, while subsequent Feature Drops will increase the Android major version to .2 and focus on introducing Android-specific features that help you be more productive for Android app development.

How to get started

Ready to try the exciting new features in Android Studio?

You can download the canary version Android Studio Koala 🐨 Feature Drop (2024.1.2) today to incorporate these new features into your workflow or try the stable version Android Studio Jellyfish 🪼. You can also install them side by side by following these instructions.

As always, your feedback is important to us – check known issues, report bugs, suggest improvements, and be part of our vibrant community on LinkedIn Medium, YouTube, or X. Let's build the future of Android apps together!

Source: Android Developers Blog

Introducing a new Text-To-Speech engine on Wear OS

Posted by Ouiam Koubaa – Product Manager and Yingzhe Li – Software Engineer

Today, we’re excited to announce the release of a new Text-To-Speech (TTS) engine that is performant and reliable. Text-to-speech turns text into natural-sounding speech across more than 50 languages powered by Google’s machine learning (ML) technology. The new text-to-speech engine on Wear OS uses decreased prosody ML models to bring faster synthesis on Wear OS devices.

Use cases for Wear OS’s text-to-speech can range from accessibility services, coaching cues for exercise apps, navigation cues, and reading aloud incoming alerts through the watch speaker or Bluetooth connected headphones. The engine is meant for brief interactions, so it shouldn’t be used for reading aloud a long article, or a long summary of a podcast.

How to use Wear OS’s TTS

Text-to-speech has long been supported on Android. Wear OS’s new TTS has been tuned to be performant and reliable on low-memory devices. All the Android APIs are still the same, so developers use the same process to integrate it into a Wear OS app, for example, TextToSpeech#speak can be used to speak specific text. This is available on devices that run Wear OS 4 or higher.

When the user interacts with the Wear OS TTS for the first time following a device boot, the synthesis engine is ready in about 10 seconds. For special cases where developers want the watch to speak immediately after opening an app or launching an experience, the following code can be used to pre-warm the TTS engine before any synthesis requests come in.

private fun initTtsEngine() {
    // Callback when TextToSpeech connection is set up
    val callback = TextToSpeech.OnInitListener { status ->
        if (status == TextToSpeech.SUCCESS) {
            Log.i(TAG, "tts Client Initialized successfully")


            // Get default TTS locale
            val defaultVoice = tts.voice
            if (defaultVoice == null) {
                Log.w(TAG, "defaultVoice == null")
                return@OnInitListener
            }


            // Set TTS engine to use default locale
            tts.language = defaultVoice.locale




            try {
                // Create a temporary file to synthesize sample text
                val tempFile =
                        File.createTempFile("tmpsynthesize", null, applicationContext.cacheDir)


                // Synthesize sample text to our file
                tts.synthesizeToFile(
                        /* text= */ "1 2 3", // Some sample text
                        /* params= */ null, // No params necessary for a sample request
                        /* file= */ tempFile,
                        /* utteranceId= */ "sampletext"
                )


                // And clean up the file
                tempFile.deleteOnExit()
            } catch (e: Exception) {
                Log.e(TAG, "Unhandled exception: ", e)
            }
        }
    }


    tts = TextToSpeech(applicationContext, callback)
}

When you are done using TTS, you can release the engine by calling tts.shutdown() in your activity’s onDestroy() method. This command should also be used when closing an app that TTS is used for.

Languages and Locales

By default, Wear OS TTS includes 7 pre-loaded languages in the system image: English, Spanish, French, Italian, German, Japanese, and Mandarin Chinese. OEMs may choose to preload a different set of languages. You can check what languages are available by using TextToSpeech#getAvailableLanguages(). During watch setup, if the user selects a system language that is not a pre-loaded voice file, the watch automatically downloads the corresponding voice file the first time the user connects to Wi-Fi while charging their watch.

There are limited cases where the speech output may differ from the user’s system language. For example, in a scenario where a safety app uses TTS to call emergency responders, developers might want to synthesize speech in the language of the locale the user is in, not in the language the user has their watch set to. To synthesize text in a different language from system settings, use TextToSpeech#setLanguage(java.util.Locale)

Conclusion

Your Wear OS apps now have the power to talk, either directly from the watch’s speakers or through Bluetooth connected headphones. Learn more about using TTS.

We look forward to seeing how you use Text-to-speech engine to create more helpful and engaging experiences for your users on Wear OS!

Copyright 2023 Google LLC.
SPDX-License-Identifier: Apache-2.0

Source: Android Developers Blog

Wear OS hybrid interface: Boosting power and performance

Posted by Kseniia Shumelchyk, Android Developer Relations Engineer

In collaboration with our hardware partners, we’ve continued to prioritize the Wear OS by Google user experience. As such, we’ve made fundamental design changes to the platform and substantially expanded the capabilities of the Wear OS hybrid interface that improve two key areas: power and performance.

With OnePlus Watch 2, powered with the latest version of Wear OS (Wear OS 4), the dual-chipset architecture works with our hybrid interface to get both chips to work better in tandem. This enables even more use cases to benefit from dramatically extended battery life of up to 100 hours of regular use with all functionalities accessible in Smart Mode.

Together, we’ve created a premium smartwatch experience that doesn’t compromise the advanced feature set or battery life. In this post, we’ll share how you can benefit from these changes when building experiences for Wear OS.

On the edge of innovation: redesigned smartwatch architecture

Wear OS smartwatches have a dual-chipset architecture inclusive of a powerful application processor (AP) and ultra low-power co-processor microcontroller unit (MCU). The architecture has a powerful AP capable of handling complex operations en-masse, and is seamlessly coupled with a low power MCU.

The Wear OS hybrid interface enables intelligent switching between the MCU or the AP, allowing the AP to be suspended when not needed to preserve battery life. It helps, for instance, achieve more power-efficient experiences, like sensor data processing on the MCU while the AP is asleep. At the same time, the hybrid interface provides a seamless transition between these states, keeping a rich and premium user experience without jarring transitions between power modes.

Connectivity and notification experience

To enhance connectivity-reliant interactions like notifications and phone calls, OnePlus utilized platform capabilities with the notification API in the hybrid interface, enabling the MCU to process regular notification experiences and reduce the need to activate the AP.

For example, bridged notifications will be delivered to the watch without waking up the high-performance AP. Users can read and dismiss these notifications while the watch is still powered by the MCU. The MCU can also handle wearable-specific actions in notifications, such as quick replies or remote actions.

What this means for development

You can leverage existing Wear OS APIs to get these optimizations without any added effort – no code changes required!

Notifications

The notification hybrid interface enables seamless transitions between power modes to work with the Wear OS notification stack. You get the best notification performance by using the Notification API.

Health & Fitness experiences

The Wear OS hybrid interface also elevates the fitness experience with more precise workout tracking, automatic sports recognition and smarter health data monitoring. All of these can be offered to users without compromising battery life.

Starting with Wear OS 3, developers use Health Services on Wear OS to gain access to sensor data. The health hybrid interface works under the hood to enable power optimizations by batching sensor data on the MCU and periodically updating developer apps through the Health Services API on the AP.

Watch Faces

With Wear OS 4, we launched the Watch Face Format, a declarative XML format to create customizable and power-efficient watch faces.

The platform has created capabilities to implement Watch Face Format rendering on the MCU, so using the new format helps future-proof certain watch faces to take advantage of emerging optimizations in future devices for better battery usage.

Check out the watch face format documentation and design guidelines for Wear OS watch faces.

Expand your reach with Wear OS

With the additions to the Wear OS smartwatch ecosystem and expanded device capabilities, it's an ideal time to build experiences for smartwatches that can reach more users and benefit your business.

To begin developing apps for Wear OS, try our Compose for Wear OS codelab, and check out the documentation and samples.

Read more about developer updates in Wear OS 4, and how you can get your apps ready for the latest Wear OS watches.

We can’t wait to see what experiences you’ll build!

Source: Android Developers Blog

Thank you for creating excellent apps, across devices in 2023!

Posted by Anirudh Dewani, Director of Android Developer Relations

Hello Android Developers,

As we approach the end of 2023, I wanted to take a moment to reflect on all that we've accomplished together as a community, and send a huge *thank you* for all of your work!

It's been an incredible year for Android, with many new features and improvements released as part of the platform as well as many new delightful app experiences crafted and delivered by you, all for the benefit of our users across the world. Here are just a few of the highlights:

The release of feature packed and highly performant Android 14, our most ambitious release to date.
The incredible momentum on large screens and Wear OS, fueled by hardware innovations of device makers and by the great app experiences you build for users
The growth of Compose, from being a mobile developer toolkit to Compose Everywhere, helping you build excellent apps for mobile, tablets, wear and TV,
And the growth of the entire Android Developer community around the world, and the millions of amazing apps you build for users!

I'm so proud of everything we've achieved together this year!

Your hard work and dedication continue to make Android the best mobile platform in the world, and I want to thank you for being a part of this community. Your contributions are invaluable, and I'm grateful for your continued support.

Thanks again for all that you do, and we can’t wait to see what you build next year!

Best,

Anirudh Dewani

Director, Android Developer Relations

Thank You for building excellent apps across devices! 0 PELOTO zoom SAMSUNG happyHolidays (year: Int = 2023)

Source: Android Developers Blog

Unbox 11 new Android features and updates

Android is announcing new features rolling out now and in the coming weeks.

Source: The Official Google Blog

Wear OS 4 is now stable and available on Google Pixel Watch 2!

Posted by Kseniia Shumelchyk, Android Developer Relations Engineer and Kevin Hufnagle, Android Technical Writer

Google Pixel Watch 2 is here and brings the capabilities of Wear OS 4 to users; get your app ready for the latest software and devices!

We're excited to bring Wear OS 4 and new user experiences to more devices, including the new Google Pixel Watch 2! We’re also providing updated developer tools for you to prepare your apps for Wear OS 4.

Pixel Watch 2, announced at Made by Google, will support Wear OS 4 upon its release this month. Wear OS 4 brings features and improvements to help you deliver more engaging and delightful experiences in your app.

Image of three watch faces created using the Watch Face Format

Later this year, Pixel Watches will receive a system update to Wear OS 4, further expanding the set of users who can enjoy your app’s capabilities on the latest software.

Developers can also continue to use Samsung Galaxy Watches to test their apps on Wear OS 4.

The latest version of Wear OS offers several capabilities that make it easier to develop dependable, helpful wearable experiences:

Watch Face Format

Created in partnership with Samsung, the Watch Face Format is a declarative XML format that lets you design the appearance and behavior of watch faces. There is no executable code involved in creating a watch face using the Watch Face Format, and there will be no code embedded in your watch face APK.

The Wear OS platform takes care of the logic needed to render the watch face that uses the Watch Face Format. This means that you don’t have to worry about code optimizations or battery performance. We recommend that you create your watch face using the Watch Face Format.

Watch faces created using the Watch Face Format

More seamless data transfer

On devices that support cloud backup—including Pixel Watch 2 and Pixel Watch—users can transfer data from one Wear OS watch to another using a cloud backup and restore process. You can customize the set of files in your app that the system should include in a cloud backup, so that users only restore app data that’s meaningful to them.

Additionally, Wear OS 4 allows users to transfer their watch to a new phone without needing to perform a factory reset on the watch. They complete this process when setting up the new phone, as shown in the following flow below.

If your app stores user configuration data for the watch on the old phone, you can allow the system to transfer this app data onto the new phone too. The guide on how to transfer Wear OS data to a new mobile device has more details.

The user-facing process for transferring watch data onto a new phone, when the user first connects the new phone to the watch. This example shows the experience when the user initiates the data transfer from the old phone.

Enhanced Tiles

Wear OS 4 offers enhanced capabilities for your app’s tiles. Version 1.2 of the Jetpack Tiles library introduces support for platform data bindings and animations, so you can provide even more responsive experiences to your users.

Moving images of animated tile on the left and a tile using data binding on the right

Watch faces created using the Watch Face FormatExamples of animated tile (on the left) and a tile using data binding (on the right)

Get your app ready for Wear OS 4

Wear OS 4 is based on Android 13, which is several versions newer than the current Wear OS version, so your app will need to handle the system behavior changes that take effect in Android 12 and Android 13.

Read the developer documentation to discover key behavior changes and learn how to interact with new features. We recommend you start by testing your app and releasing a compatible update, so that you’re ready when the first devices get upgraded to Wear OS 4. This gives your app a basic but critical level of quality that provides a good experience for users.

Wear OS 4 emulator

Today we’ve also released updated system images for Wear OS emulators, available starting in Android Studio Hedgehog to help test your apps on Wear OS 4.

The new Wear OS 4 emulator doesn’t support native 32-bit code, so if your app uses native code, make sure that it includes both 32-bit and 64-bit native libraries. This will also prepare your app for upcoming 64-bit only hardware.

Learn more

To begin developing apps for Wear OS, try our Compose for Wear OS codelab, and check out the documentation and samples.

Discover even more! View the Wear OS session from Google I/O, and read about the latest Jetpack releases for Wear OS.

There’s never been a better time to get your app ready for Wear OS 4 and all the latest Wear OS watches. We can’t wait to see your apps on Wear OS 4 and what experiences you’ll build!

Source: Android Developers Blog

Compose for Wear OS and Tiles 1.2 libraries are now stable: check out new features!

Posted by Anna Bernbaum, Product Manager and Kseniia Shumelchyk, Android Developer Relations Engineer

We’re excited to announce that version 1.2 of Compose for Wear OS and Wear Tiles libraries have reached the stable milestone. This makes it easier than ever to use these modern APIs to build beautiful and engaging apps for Wear OS.

We continue to evolve Android Jetpack libraries for Wear OS with new features and improvements to streamline development, including support for the latest Wear OS 4 release.

Many developers are already leveraging the powerful tools and intuitive APIs to create exceptional experiences for Wear OS. Partners like Peloton and Deezer were able to quickly build a watch experience and are seeing the impact on their feature-adoption and user engagement.

"The Wear OS app was our first usage of Compose in production, we really enjoyed how much more productive it made us.”
– Stefan Haacker, a senior Android engineer at Peloton.

Compose for Wear OS and Wear Tiles complement one another. Use Wear Tiles to define the experience in your app’s tiles, and use Compose for Wear OS to build UIs across the more detailed screens in your app. Both sets of APIs offer material components and layouts that ensure your app experience on Wear OS is coherent and follows our best practices.

Now, let’s look into key features of version 1.2 of Jetpack libraries for Wear OS.

Compose for Wear OS 1.2 release

Compose for Wear OS version 1.2 contains new components and brings improvements to tooling, as well as the usability and accessibility of existing components:

Expandable Items

The new expandableItem, expandableItems and expandableButton components provide a simple way to fold and unfold content on demand. Use these components to hide detailed information on long pages or expanded sections by default. This design pattern allows users to focus on essential content and choose when to view the more detailed information.

This pattern enables apps to include high-density content while preserving the key principles of wearables – compactness and glanceability.

Moving images of expanding list and expanding text using the new component — *Example of expanding list and expanding text using the new component*

The component can be used for expanding lists within ScalingLazyColumn, so expandableButton collapses after the content in expandableItems is revealed in one smooth option. Another use case is expanding the content of a single item, such as Text, that would otherwise contain too many lines to show all at once when the screen first loads.

Swipe to Reveal

A new experimental API has been added to support the SwipeToReveal pattern, as a way to add up to 2 secondary actions when the composable is swiped to the left. It also provides support for users to undo the secondary actions that they take. This component is intended for use cases where the existing ‘long press’ pattern is not ideal.

Note that this feature is distinct from swipe-to-dismiss, which is used to navigate back to the previous screen.

Compose Previews for Wear OS

In version 1.2 we’ve added device configurations to the set of Compose Preview annotations that you use when evaluating how a design looks and behaves on a variety of devices.

We added a number of custom Wear Preview annotations for different watch shapes and sizes: WearPreviewSmallRound, WearPreviewLargeRound, WearPreviewSquare. We’ve also added the WearPreviewDevices, WearPreviewFontScales annotations to check your app against multiple device configurations and types at once. Use these new annotations to instantly verify how your app’s layout behaves on a variety of Wear OS devices.

Image showing WearPreviewDevices and WearPreviewFontScales annotations used for Horologist VolumeScreen preview — *WearPreviewDevices and WearPreviewFontScales annotations used for Horologist VolumeScreen preview*

Wear Compose tooling is available within a separate dependency androidx.wear.compose.ui.tooling.preview that you’ll need to include in addition to general Compose dependencies.

UX and accessibility improvements

The 1.2 release also introduced numerous improvements for user experience and accessibility:

Reduce-motion setting is now supported. When setting switched on it will disable scaling and fading animations in ScalingLazyColumn, and turn off the shimmering effect and wipe-off motion on placeholders.
HierarchicalFocusCoordinator - new experimental composable that enables marking sub-trees of the composition as focus enabled or focus disabled. Use this to control which element receives rotary scroll events, such as multiple ScalingLazyColumns in a HorizontalPage
PickerGroup - a new composable designed to combine multiple pickers together. It handles focus between the pickers using the HierarchicalFocusCoordinator API and enables auto-centering of Picker items. It’s already integrated in prebuilt Date and Time pickers from Horologist: check out some examples.
Picker has a new userScrollEnabled parameter, which determines if picker should be scrollable and disables scrolling when not focused.
The shimmer and wipe-off animations for placeholder now apply the wipe-off effect immediately when the content is ready.
Stepper has an additional parameter, enableRangeSemantics, that allows customization of semantics, such as disabling default range semantics when required.

Other changes

ScalingLazyColumn and associated classes have migrated from the material package to the foundation.lazy package, as a preparation for a new Material3 library. You can use this migration script to update your code seamlessly.

The Horologist library enhances the implementation of snap behavior to a ScalingLazyColumn, TimePicker and DatePicker when the user interacts with a rotary crown. The rotaryWithFling modifier was deprecated in favor of rotaryWithScroll which includes fling behavior by default. Check out rotaryWithScroll and rotaryWithSnap reference documentation for details.

Moving image of Snap and fling behavior for scrolling list — *Snap and fling behavior for scrolling list*

Tiles 1.2 release

Tiles are designed to give users fast, predictable access to the information and actions they rely on most. Version 1.2 of the Jetpack Tiles Library introduces support for platform data bindings and animations so you can provide even more responsive experiences to your users.

Moving image of Tiles carousel on Wear Os — *Tiles carousel on Wear OS*

Platform data bindings

Version 1.2 introduces support dynamic expressions that link elements of your tile to platform data sources. If your tile uses platform data sources such as heart rate, or, step count, or time, your tile can be updated up to once per second.

Moving image of a tile using data binding — *Examples of a tile using data binding*

Animations

The new version of tiles also adds support for animations. You can use tween animations to create smooth transitions when part of your layout changes, and use transition animations to animate new or disappearing elements from the tile.

Moving images of animated tiles — *Examples of animated tiles*

Partial tile updates

We have also now enabled partial tile updates, meaning that we will only update the part of your tile that has been updated, not the entire layout. This allows you to update part of your tile, while an animation is playing in another part, without disrupting that animation.

Learn more

Get started with hands-on experience trying our codelab to create your first Tile and Compose for Wear OS codelab.

We’ve already updated our samples and Horologist libraries to work with the latest version of Jetpack libraries for Wear OS. Also make sure to check out the documentation for Tiles and Compose for Wear OS to learn more about best practices when building apps for wearables.

Provide feedback

We continue to evolve our APIs with the features you’ve been asking for. Please do continue providing us feedback on the issue tracker , and join the Kotlin Slack #compose-wear channel to connect with the Google team and developer community.

Start building for Wear OS now

Discover even more by taking a look at our developer site and reading the latest Wear OS announcements from Google I/O!

Source: Android Developers Blog

Deezer increased its monthly active users 4X after improving multi-device support

Posted by the Android team

Deezer is a global music streaming platform that provides users access to over 110 million tracks. Deezer aims to make its application easily accessible, letting users listen to their audio when, where, and how they want. With the growing popularity of Wear OS devices and large screens and foldables, the Deezer team saw an opportunity to give its users more ways to stream by enhancing its multi-device support.

We’re focused on delivering a consistently great UX on as many devices as possible.” — Hugo Vignaux, senior product manager at Deezer

Increasing smart watch support

Over the past few years, users increasingly requested Deezer to make its app available on Wear OS. During this time, the Deezer team had also seen rapid growth in the wearable market.

“The Wear OS market was growing thanks to the Fitbit acquisition by Google, the Pixel watch announcement, and the switch to Wear OS on Galaxy watches,” said Hugo Vignaux, a senior product manager at Deezer. “It was perfect timing because Google raised the opportunity with us to invest in Wear OS by joining the Media Experience Program in 2022.”

Deezer’s developers initially focused on providing instant, easy access to users’ personalized playlists from the application. To do this, engineers streamlined the app’s Wear OS UI, making it easier for users to control the app from their wrist. They also implemented a feature that allowed users to download their favorite Deezer playlists straight to their smartwatches, making offline playback possible without requiring a phone or an internet connection.

The Deezer team relied on Google’s Horologist and its Media Toolkit during development. Horologist and its libraries guided the team and ensured updates to the UI adhered to Wear best practices. It also made rolling out features like audio and bluetooth management much easier.

“The player view offered by the Media Toolkit was a source of inspiration and guaranteed that the app’s code quality was up to par,” said Hugo. “It also allowed us to focus on unit testing and resiliency rather than developing new features from scratch.”

More support for large screens and foldables

Before updating the app, Deezer’s UX wasn’t fully optimized for large screens and foldables. With this latest update, Deezer developers created special layouts for multitasking on large screens, like tablets and laptops, and used resizable emulators to optimize the app’s resizing capabilities for each screen on foldables.

“Supporting large screens means we can better fit multiple windows on a screen,” said Geoffrey Métais, engineering manager at Deezer. “This allows users to easily switch between apps, which is good because Deezer doesn’t require a user's full attention for them to make use of its UI.”

On tablets, Deezer developers split pages that were displayed vertically to be displayed horizontally. Developers also implemented a navigation rail and turned some lists into grids. These simple quality-of-life updates improved UX by giving users an easier way to click through the app.

Making these changes was easy for developers thanks to the Jetpack WindowManager library. “The WindowManager library made it simple to adapt our UI to different screen sizes,” said Geoffrey. “It leverages Jetpack Compose’s modularity to adapt to any screen size. And Compose code stays simple and consistent despite addressing a variety of different configurations.”

Updates to large screens and foldables and Wear OS were all created using Jetpack Compose and Compose for Wear OS, respectively. With Jetpack Compose, Deezer developers were able to efficiently create and implement a design system that focused on technical issues within the new app. The Deezer team attributes their increased productivity with Compose to Composable functions, which lets developers reuse code segments, and Android Studio, which helps developers iterate on features faster.

“The combination of a proper Design System with Jetpack Compose’s modularity and reactive paradigms is a very smart and efficient solution to improve usability without losing development productivity,” said Geoffrey.

'With the new capabilities of Wear OS 3, we’ve optimized the Deezer experience for the next generation of smartwatches, letting our users listen to their music anywhere, anytime.' — Hugo Vignaux, senior product manager at Deezer

The impact of increased multi-device support

Increasing multi-device support was easy for Deezer developers thanks to the tools and resources offered by Google. The updates the Deezer team made across screens improved the app’s UI, making it easier for users to navigate the app and listen to audio on their own terms.

Since updating for Wear OS and other Android devices, the Deezer team saw a 4X increase in user engagement and received positive feedback from its community.

“Developing for WearOS and across devices was great thanks to the help of the Google team and the availability of libraries and APIs that helped us deliver some great features, such as Horologist and its Media Toolkit. All those technical assets were very well documented and the Google team’s dedication was tremendous,” said Hugo.

Get started

Learn how you can start developing for Wear OS and other Android devices today.

Source: Android Developers Blog

Peloton increased its multi-device support and saw an uptick in user engagement

Posted by the Android team

The Peloton App makes it easy for people to work out wherever they want, whenever they want. From living room yoga classes to guided audio runs outdoors, Peloton strives to create an engaging exercise experience that works for anyone, anywhere.

For Peloton, creating convenient workouts means making the Peloton App more accessible across surfaces. So after receiving numerous requests to upgrade its Android app experience from its community, along with the Pixel Watch announcement at Google I/O in 2022, the Peloton team saw an opportunity to boost the app’s support across the entire Android ecosystem, ensuring its Members receive a seamless Peloton experience on all their devices.

Building the Wear OS experience

Peloton developers began updating the app’s multi-device support by creating a modern watch application for Wear OS devices using Compose for Wear OS. With the Compose toolkit, Peloton developers were able to quickly build a watch experience that met Wear OS guidelines. “The Wear OS app was our first usage of Compose in production,” said Stefan Haacker, a senior Android engineer at Peloton. “We really enjoyed how much more productive it made us.”

The Peloton team released the first wearable app version just after the Pixel Watch launched. They worked tirelessly to get the app ready between the announcement of the Pixel Watch and its launch. Thanks to the Jetpack Compose toolkit, Peloton developers were able to rapidly and efficiently prepare the app in record time.

The new wearable app gave Peloton Members more options for monitoring their heart rate in real time. Using the Data Layer API to synchronize information between wearables and the Peloton App, Members can now view their heart rate across devices—from their phones to their watches to their bikes—as they take a Peloton class.

“Before the Wear OS app was released, only a small percentage of Android Members worked out with a heart rate monitor (HRM). After releasing Peloton on Wear OS, the app had a 6X increase in HRM usage in just a few months,” said Stefan. “For Peloton, HRM usage correlates with a better user experience, increased user engagement, and more workouts a month.”

With more Members tracking their health and fitness data through the new Peloton app, it was important for the Peloton team to give them better access to that data. That’s why Peloton was excited to partner with Google to offer Health Connect integration from day one, giving its users a simpler way to consolidate and share their fitness data across applications.

Increased support across devices

Peloton developers wanted to embrace the uniqueness of each device across the Android ecosystem and focus on the individual benefits that their form factors could offer. With this mindset, it was easier for the Peloton team to create a flexible UI that could adapt to various screens.

“We had to stop developing and designing with rigid device categories in mind,” said Ward Bonnefond, a senior staff software engineer at Peloton. “Phones these days no longer have just a single rectangular screen.”

The Peloton team began optimizing for large screens and foldables by improving how the app handles window resizing across orientations and devices. Using resizable emulators, Peloton developers were able to ensure the app behaved as expected with different configurations and screen sizes.

“We used RecyclerViews to determine the number of columns the app displays at runtime based on the available screen size,” said Ward. “We removed restrictions on activity resizing and orientation locking so that our app would function properly in full screen, split screen, resizable floating windows, and foldables.”

Peloton developers used Jetpack WindowManager to support foldable-specific use cases, like tabletop mode for the app’s video player. The window manager library made it easy for developers to place a video above a device’s fold and workout metrics below it.

Peloton developers also streamlined the login process on Android TV. Instead of forcing Members to fumble over typing their credentials with a remote, they can now login through the Peloton App on their phone to quickly connect with their TV.

Quote card with text reads, 'With the Android SDK and Jetpack Libraries, it’s really easy to create a flexible UI that adapts to the different screen size.' — Ward Bonnefond, senior staff software engineer at Peloton

More devices, more opportunities

Since launching the all-new Wear OS application and enhancing support across Android devices, Peloton has seen an uptick in total workouts taken on the Android platform. Although other factors were at play, the Peloton team attributes much of that increase to the new wearable application.

“There are so many different devices with varying capabilities in the Android ecosystem, like phones, watches, tablets, TVs and more,” said Ward. “At the end of the day, we want the Peloton App to be awesome wherever Members use it.”

Get started

Learn how you can start developing for Wear OS and other Android devices today.