Tag Archives: Android

TalkBack uses Gemini Nano to increase image accessibility for users with low vision

Posted by Terence Zhang – Developer Relations Engineer and Lisie Lillianfeld - Product Manager

TalkBack is Android’s screen reader in the Android Accessibility Suite that describes text and images for Android users who have blindness or low vision. The TalkBack team is always working to make Android more accessible. Today, thanks to Gemini Nano with multimodality, TalkBack automatically provides users with blindness or low vision more vivid and detailed image descriptions to better understand the images on their screen.

Increasing accessibility using Gemini Nano with multimodality

Advancing accessibility is a core part of Google’s mission to build for everyone. That’s why TalkBack has a feature to describe images when developers didn’t include descriptive alt text. This feature was powered by a small ML model called Garcon. However, Garcon produced short, generic responses and couldn’t specify relevant details like landmarks or products.

The development of Gemini Nano with multimodality was the perfect opportunity to use the latest AI technology to increase accessibility with TalkBack. Now, when TalkBack users opt in on eligible devices, the screen reader uses Gemini Nano’s new multimodal capabilities to automatically provide users with clear, detailed image descriptions in apps including Google Photos and Chrome, even if the device is offline or has an unstable network connection.

“Gemini Nano helps fill in missing information,” said Lisie Lillianfeld, product manager at Google. “Whether it’s more details about what’s in a photo a friend sent or the style and cut of clothing when shopping online.”

Going beyond basic image descriptions

Here’s an example that illustrates how Gemini Nano improves image descriptions: When Garcon is presented with a panorama of the Sydney, Australia shoreline at night, it might read: “Full moon over the ocean.” Gemini Nano with multimodality can paint a richer picture, with a description like: “A panoramic view of Sydney Opera House and the Sydney Harbour Bridge from the north shore of Sydney, New South Wales, Australia.”

“It's amazing how Nano can recognize something specific. For instance, the model will recognize not just a tower, but the Eiffel Tower,” said Lisie. “This kind of context takes advantage of the unique strengths of LLMs to deliver a helpful experience for our users.”

Using an on-device model like Gemini Nano was the only feasible solution for TalkBack to provide automatically generated detailed image descriptions for images, even while the device is offline.

“The average TalkBack user comes across 90 unlabeled images per day, and those images weren't as accessible before this new feature,” said Lisie. The feature has gained positive user feedback, with early testers writing that the new image descriptions are a “game changer” and that it’s “wonderful” to have detailed image descriptions built into TalkBack.


Gemini Nano with multimodality was critical to improving the experience for users with low vision. Providing detailed on-device image descriptions wouldn’t have been possible without it. — Lisie Lillianfeld, Product Manager at Google

Balancing inference verbosity and speed

One important decision the Android accessibility team made when implementing Gemini Nano with multimodality was between inference verbosity and speed, which is partially determined by image resolution. Gemini Nano with multimodality currently accepts images in either 512 pixels or 768 pixels.

“The 512-pixel resolution emitted its first token almost two seconds faster than 768 pixels, but the output wasn't as detailed,” said Tyler Freeman, a senior software engineer at Google. “For our users, we decided a longer, richer description was worth the increased latency. We were able to hide the perceived latency a bit by streaming the tokens directly to the text-to-speech system, so users don’t have to wait for the full text to be generated before hearing a response.”

A hybrid solution using Gemini Nano and Gemini 1.5 Flash

TalkBack developers also implemented a hybrid AI solution using Gemini 1.5 Flash. With this server-based AI model, TalkBack can provide the best of on-device and server-based generative AI features to make the screen reader even more powerful.

When users want more details after hearing an automatically generated image description from Gemini Nano, TalkBack gives the user an option to listen to more by running the image through Gemini Flash. When users focus on an image, they can use a three-finger tap to open the TalkBack menu and select the “Describe Image” option to send the image to Gemini 1.5 Flash on the server and get even more details.

By combining the unique advantages of both Gemini Nano's on-device processing with the full power of cloud-based Gemini 1.5 Flash, TalkBack provides blind and low-vision Android users a helpful and informative experience with images. The “describe image” feature powered by Gemini 1.5 Flash launched to TalkBack users on more Android devices, so even more users can get detailed image descriptions.


Animated UI example of TalkBack in action, describing a photo of a sunny view of Sydney Harbor, Australia, with the Sydney Opera House and Sydney Harbour Bridge in the frame.

Compact model, big impact

The Android accessibility team recommends developers looking to use the Gemini Nano with multimodality prototype and test on a powerful, server-side model first. There developers can understand the UX faster, iterate on prompt engineering, and get a better idea of the highest quality possible using the most capable model available.

While Gemini Nano with multimodality can include missing context to improve image descriptions, it’s still best practice for developers to provide detailed alt text for all images on their apps or websites. If the alt text is not provided, TalkBack can help fill in the gaps.

The Android accessibility team’s goal is to create inclusive and accessible features, and leveraging Gemini Nano with multimodality to provide vivid and detailed image descriptions automatically is a big step towards that. Furthermore, their hybrid approach towards AI, combining the strengths of both Gemini Nano on device and Gemini 1.5 Flash in the server, showcases the transformative potential of AI in promoting inclusivity and accessibility and highlights Google's ongoing commitment to building for everyone.

Get started

Learn more about Gemini Nano for app development.


This blog post is part of our series: Spotlight Week on Android 15, where we provide resources — blog posts, videos, sample code, and more — all designed to help you prepare your apps and take advantage of the latest features in Android 15. You can read more in the overview of Spotlight Week: Android 15, which will be updated throughout the week.

Our first Spotlight Week: diving into Android 15

Posted by Aaron Labiaga- Android Developer Relations Engineer

By now, you’ve probably heard the news: Android 15 was just released earlier today to AOSP. To celebrate, we’re kicking off a new series called “Spotlight Week” where we’ll shine a light on technical areas across Android development and equip you with the tools you need to take advantage of each area.

The Android 15 "Spotlight Week" will provide resources — blog posts, videos, sample code, and more — all designed to help you prepare your apps and take advantage of the latest features. These changes strive to improve the Android ecosystem, but updating the OS comes with potential app compatibility implications and integrations that require detailed guidance.

Here’s what we’re covering this week in our Spotlight Week on Android 15:


    The Android 15 summary page outlines what a developer needs to know about what is new in the release, behavioral changes affecting all apps, and changes applicable only when targeting the new SDK level 35.


  • Building for the future of Android, an in-depth video (Wednesday, Sept 4)

  • Foreground services and a live Android 15 Q&A (Thursday, September 5): Foreground services changes are coming in Android 15, and we’re introducing a new foreground service type, updating the exemption scenarios that allow a foreground service to start from the background, and updating the max duration of certain foreground service types. These changes are intended to improve user experience by preventing apps from misusing foreground service that may drain a user’s battery. Plus we’ll have a live Q&A.

  • Passkeys and Picture-in-Picture (Friday, September 6): Passkeys enable a more streamlined and secured means of authenticating your users. Learn more about passkeys through our sample code and about the updates made to further simplify the login process in Android 15. Plus, we're highlighting a Picture-in-Picture sample code that is applicable to apps with video functionality.

That’s just a taste of what we’re covering in our Spotlight Week on Android 15. Keep checking back to this blog post for updates, where we’ll be adding links and more throughout the week. Plus, follow Android Developers on X and Android by Google at Linkedin throughout the week to hear even more about Android 15.

Our first Spotlight Week: diving into Android 15

Posted by Aaron Labiaga- Android Developer Relations Engineer

By now, you’ve probably heard the news: Android 15 was just released earlier today to AOSP. To celebrate, we’re kicking off a new series called “Spotlight Week” where we’ll shine a light on technical areas across Android development and equip you with the tools you need to take advantage of each area.

The Android 15 "Spotlight Week" will provide resources — blog posts, videos, sample code, and more — all designed to help you prepare your apps and take advantage of the latest features. These changes strive to improve the Android ecosystem, but updating the OS comes with potential app compatibility implications and integrations that require detailed guidance.

Here’s what we’re covering this week in our Spotlight Week on Android 15:


    The Android 15 summary page outlines what a developer needs to know about what is new in the release, behavioral changes affecting all apps, and changes applicable only when targeting the new SDK level 35.


  • Building for the future of Android, an in-depth video (Wednesday, Sept 4)

  • Foreground services and a live Android 15 Q&A (Thursday, September 5): Foreground services changes are coming in Android 15, and we’re introducing a new foreground service type, updating the exemption scenarios that allow a foreground service to start from the background, and updating the max duration of certain foreground service types. These changes are intended to improve user experience by preventing apps from misusing foreground service that may drain a user’s battery. Plus we’ll have a live Q&A.

  • Passkeys and Picture-in-Picture (Friday, September 6): Passkeys enable a more streamlined and secured means of authenticating your users. Learn more about passkeys through our sample code and about the updates made to further simplify the login process in Android 15. Plus, we're highlighting a Picture-in-Picture sample code that is applicable to apps with video functionality.

That’s just a taste of what we’re covering in our Spotlight Week on Android 15. Keep checking back to this blog post for updates, where we’ll be adding links and more throughout the week. Plus, follow Android Developers on X and Android by Google at Linkedin throughout the week to hear even more about Android 15.

Android 15 is released to AOSP

Posted by Matthew McCullough – VP of Product Management, Android Developer

Today we're releasing Android 15 and making the source code available at the Android Open Source Project (AOSP). Android 15 will be available on supported Pixel devices in the coming weeks, as well as on select devices from Samsung, Honor, iQOO, Lenovo, Motorola, Nothing, OnePlus, Oppo, realme, Sharp, Sony, Tecno, vivo, and Xiaomi in the coming months.

We're proud to continue our work in open source through the AOSP. Open source allows anyone to build upon and contribute to Android, resulting in devices that are more diverse and innovative. You can leverage your app development skills in Android Studio with Jetpack Compose to create applications that thrive across the entire ecosystem. You can even examine the source code for a deeper understanding of how Android works.

Android 15 continues our mission of building a private and secure platform that helps improve your productivity while giving you new capabilities to produce beautiful apps, superior media and camera experiences, and an intuitive user experience, particularly on tablets and foldables.

Starting today, we're kicking off a new educational series called Spotlight Weeks, where we dive into technical topics across Android, beginning with a week of content on Android 15. Check out what we'll be covering throughout the week, as well as today's deep dive into edge-to-edge.

Improving your developer experience

While most of our work to improve your productivity centers around tools like Android Studio, Jetpack Compose, and the Android Jetpack libraries, each new Android platform release includes quality-of-life updates to improve the development experience. For example, Android 15 gives you new insights and telemetry to allow you to further tune your app experience, so you can make changes that improve the way your app runs on any platform release.

Improving typography and internationalization

Android helps you make beautiful apps that work well across the global diversity of the Android ecosystem.

    • You can now create a FontFamily instance from variable fonts in Android 15 without having to specify wght and ital axes using the buildVariableFamily API; the text renderer will automatically adjust the values of the wght and ital axes to match the displaying text with compatible fonts.
    • The font file in Android 15 for Chinese, Japanese, and Korean (CJK) languages, NotoSansCJK, is now a variable font, opening up new possibilities for creative typography.

Camera and media improvements

Each Android release helps you bring superior media and camera experiences to your users.

    • For screens that contain both HDR and SDR content, Android 15 allows you to control the HDR headroom with setDesiredHdrHeadroom to prevent SDR content from appearing too washed-out.
    • Android 15 supports intelligently adjusting audio loudness and dynamic range compression levels for apps with AAC audio content that contains loudness metadata so that audio levels can adapt to user devices and surroundings. To enable, instantiate a LoudnessCodecController with the audio session ID from the associated AudioTrack.
    • Low Light Boost in Android 15 adjusts the exposure of the Preview stream in low-light conditions, enabling enhanced image previews, scanning QR codes in low light, and more.
    • Advanced flash strength adjustments in Android 15 enable precise control of flash intensity in both SINGLE and TORCH modes while capturing images.
    • Android 15 extends Universal MIDI Packets support to virtual MIDI apps, enabling composition apps to control synthesizer apps as a virtual MIDI 2.0 device just like they would with an USB MIDI 2.0 device.

Improving the user experience

We continue to refine the Android user experience with every release, while working to improve performance and battery life. Here is just some of what Android 15 brings to make the experience more intuitive, performant, and accessible.

Privacy and security enhancements

Privacy and security are at the core of everything we do, and we work to make meaningful improvements to protect your apps and our users with each platform release.

Get your apps, libraries, tools, and game engines ready!

If you develop an SDK, library, tool, or game engine, it's particularly important to prepare any necessary updates immediately to prevent your downstream app and game developers from being blocked by compatibility issues and allow them to target the latest SDK features. Please let your developers know if updates are needed to fully support Android 15.

Testing your app involves installing your production app using Google Play or other means onto a device or emulator running Android 15. Work through all your app's flows and look for functional or UI issues. Review the behavior changes to focus your testing. Here are several changes to consider that apply even if you don't yet target Android 15:

    • Package stopped state changes - Android 15 updates the behavior of the package FLAG_STOPPED state to keep apps stopped until the user launches or indirectly interacts with the app.
    • Support for 16KB page sizes - Beginning with Android 15, 16 KB page size support will be available on select devices as a developer option. Additionally, Android Studio also offers an emulator system image with 16 KB support through the SDK manager. If your app or library uses the NDK, either directly or indirectly through a library, you can use the developer option in the QPR beta or the Android 15 emulator system image to test and fix applications to prepare for Android devices with 16 KB page sizes in the near future.
    • Removed legacy emoji font file - Some Android 15 devices such as Pixel will no longer have the bitmap NotoColorEmojiLegacy.ttf file included for compatibility since Android 13 and will only have the default vector file.

Please thoroughly exercise libraries and SDKs that your app is using during your compatibility testing. You may need to update to current SDK versions or reach out to the developer for help if you encounter any issues.

Once you’ve published the Android 15-compatible version of your app, you can start the process to update your app's targetSdkVersion.

App compatibility

We’re working to make updates faster and smoother with each platform release by prioritizing app compatibility. In Android 15 we’ve made most app-facing changes opt-in until your app targets SDK version 35. This gives you more time to make any necessary app changes.

To make it easier for you to test the opt-in changes that can affect your app, based on your feedback we’ve made many of them toggleable again this year. With the toggles, you can force-enable or disable the changes individually from Developer options or adb. Check out how to do this, here.

App compatibility toggles in Developer Options on Android 15
App compatibility toggles in Developer Options

To help you migrate your app to target Android 15, the Android SDK Upgrade Assistant within the latest Android Studio Koala Feature Drop release now covers android 15 API changes and walks you through the steps to upgrade your targetSdkVersion.

Android SDK upgrade assistant in Android Studio Koala feature drop
Android SDK upgrade assistant in Android Studio Koala feature drop

Get started with Android 15

If you have a supported Pixel device, you will receive the public Android 15 over the air update when it becomes available. If you don't want to wait, you can get the most recent quarterly platform release (QPR) beta by joining the Android 15 QPR beta program at any time.

If you're already in the QPR beta program on a Pixel device that supports the next Android release, you'll likely have been offered the opportunity to install the first Android 15 QPR beta update. If you want to opt-out of the beta program without wiping your device, don't install the beta and instead wait for an update to the release version when it is made available on your Pixel device. Once you've applied the stable release update, you can opt out without a data wipe as long as you don't apply the next beta update.

Stay tuned for the next five days of our Spotlight Week on Android 15, where we'll be covering topics like edge-to-edge, passkeys, updates to foreground services, picture-in-picture, and more. Follow along on our blog, X, LinkedIn or YouTube channels. Thank you again to everyone who participated in our Android developer preview and beta program. We're looking forward to seeing how your apps take advantage of the updates in Android 15.

For complete information, visit the Android 15 developer site.


Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.

Android 15 is released to AOSP

Posted by Matthew McCullough – VP of Product Management, Android Developer

Today we're releasing Android 15 and making the source code available at the Android Open Source Project (AOSP). Android 15 will be available on supported Pixel devices in the coming weeks, as well as on select devices from Samsung, Honor, iQOO, Lenovo, Motorola, Nothing, OnePlus, Oppo, realme, Sharp, Sony, Tecno, vivo, and Xiaomi in the coming months.

We're proud to continue our work in open source through the AOSP. Open source allows anyone to build upon and contribute to Android, resulting in devices that are more diverse and innovative. You can leverage your app development skills in Android Studio with Jetpack Compose to create applications that thrive across the entire ecosystem. You can even examine the source code for a deeper understanding of how Android works.

Android 15 continues our mission of building a private and secure platform that helps improve your productivity while giving you new capabilities to produce beautiful apps, superior media and camera experiences, and an intuitive user experience, particularly on tablets and foldables.

Starting today, we're kicking off a new educational series called Spotlight Weeks, where we dive into technical topics across Android, beginning with a week of content on Android 15. Check out what we'll be covering throughout the week, as well as today's deep dive into edge-to-edge.

Improving your developer experience

While most of our work to improve your productivity centers around tools like Android Studio, Jetpack Compose, and the Android Jetpack libraries, each new Android platform release includes quality-of-life updates to improve the development experience. For example, Android 15 gives you new insights and telemetry to allow you to further tune your app experience, so you can make changes that improve the way your app runs on any platform release.

Improving typography and internationalization

Android helps you make beautiful apps that work well across the global diversity of the Android ecosystem.

    • You can now create a FontFamily instance from variable fonts in Android 15 without having to specify wght and ital axes using the buildVariableFamily API; the text renderer will automatically adjust the values of the wght and ital axes to match the displaying text with compatible fonts.
    • The font file in Android 15 for Chinese, Japanese, and Korean (CJK) languages, NotoSansCJK, is now a variable font, opening up new possibilities for creative typography.

Camera and media improvements

Each Android release helps you bring superior media and camera experiences to your users.

    • For screens that contain both HDR and SDR content, Android 15 allows you to control the HDR headroom with setDesiredHdrHeadroom to prevent SDR content from appearing too washed-out.
    • Android 15 supports intelligently adjusting audio loudness and dynamic range compression levels for apps with AAC audio content that contains loudness metadata so that audio levels can adapt to user devices and surroundings. To enable, instantiate a LoudnessCodecController with the audio session ID from the associated AudioTrack.
    • Low Light Boost in Android 15 adjusts the exposure of the Preview stream in low-light conditions, enabling enhanced image previews, scanning QR codes in low light, and more.
    • Advanced flash strength adjustments in Android 15 enable precise control of flash intensity in both SINGLE and TORCH modes while capturing images.
    • Android 15 extends Universal MIDI Packets support to virtual MIDI apps, enabling composition apps to control synthesizer apps as a virtual MIDI 2.0 device just like they would with an USB MIDI 2.0 device.

Improving the user experience

We continue to refine the Android user experience with every release, while working to improve performance and battery life. Here is just some of what Android 15 brings to make the experience more intuitive, performant, and accessible.

Privacy and security enhancements

Privacy and security are at the core of everything we do, and we work to make meaningful improvements to protect your apps and our users with each platform release.

Get your apps, libraries, tools, and game engines ready!

If you develop an SDK, library, tool, or game engine, it's particularly important to prepare any necessary updates immediately to prevent your downstream app and game developers from being blocked by compatibility issues and allow them to target the latest SDK features. Please let your developers know if updates are needed to fully support Android 15.

Testing your app involves installing your production app using Google Play or other means onto a device or emulator running Android 15. Work through all your app's flows and look for functional or UI issues. Review the behavior changes to focus your testing. Here are several changes to consider that apply even if you don't yet target Android 15:

    • Package stopped state changes - Android 15 updates the behavior of the package FLAG_STOPPED state to keep apps stopped until the user launches or indirectly interacts with the app.
    • Support for 16KB page sizes - Beginning with Android 15, 16 KB page size support will be available on select devices as a developer option. Additionally, Android Studio also offers an emulator system image with 16 KB support through the SDK manager. If your app or library uses the NDK, either directly or indirectly through a library, you can use the developer option in the QPR beta or the Android 15 emulator system image to test and fix applications to prepare for Android devices with 16 KB page sizes in the near future.
    • Removed legacy emoji font file - Some Android 15 devices such as Pixel will no longer have the bitmap NotoColorEmojiLegacy.ttf file included for compatibility since Android 13 and will only have the default vector file.

Please thoroughly exercise libraries and SDKs that your app is using during your compatibility testing. You may need to update to current SDK versions or reach out to the developer for help if you encounter any issues.

Once you’ve published the Android 15-compatible version of your app, you can start the process to update your app's targetSdkVersion.

App compatibility

We’re working to make updates faster and smoother with each platform release by prioritizing app compatibility. In Android 15 we’ve made most app-facing changes opt-in until your app targets SDK version 35. This gives you more time to make any necessary app changes.

To make it easier for you to test the opt-in changes that can affect your app, based on your feedback we’ve made many of them toggleable again this year. With the toggles, you can force-enable or disable the changes individually from Developer options or adb. Check out how to do this, here.

App compatibility toggles in Developer Options on Android 15
App compatibility toggles in Developer Options

To help you migrate your app to target Android 15, the Android SDK Upgrade Assistant within the latest Android Studio Koala Feature Drop release now covers android 15 API changes and walks you through the steps to upgrade your targetSdkVersion.

Android SDK upgrade assistant in Android Studio Koala feature drop
Android SDK upgrade assistant in Android Studio Koala feature drop

Get started with Android 15

If you have a supported Pixel device, you will receive the public Android 15 over the air update when it becomes available. If you don't want to wait, you can get the most recent quarterly platform release (QPR) beta by joining the Android 15 QPR beta program at any time.

If you're already in the QPR beta program on a Pixel device that supports the next Android release, you'll likely have been offered the opportunity to install the first Android 15 QPR beta update. If you want to opt-out of the beta program without wiping your device, don't install the beta and instead wait for an update to the release version when it is made available on your Pixel device. Once you've applied the stable release update, you can opt out without a data wipe as long as you don't apply the next beta update.

Stay tuned for the next five days of our Spotlight Week on Android 15, where we'll be covering topics like edge-to-edge, passkeys, updates to foreground services, picture-in-picture, and more. Follow along on our blog, X, LinkedIn or YouTube channels. Thank you again to everyone who participated in our Android developer preview and beta program. We're looking forward to seeing how your apps take advantage of the updates in Android 15.

For complete information, visit the Android 15 developer site.


Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.

Google Maps improved download reliability by 10% using user initiated data transfer API

Posted by Alice Yuan – Developer Relations Engineer, in collaboration with Software Engineers – Matthew Valgenti and Emma Li – at Google

What is user initiated data transfer?

In Android 14 we introduced user-initiated data transfer jobs, or UIDT. You can use the new API setUserInitiated in JobScheduler to specify that the job is a user-initiated data transfer job. This API is helpful for use cases that require long-duration (>10 minutes), user-initiated transfer of data over network. UIDT is also an alternative API to using a dataSync foreground service, which has new timeout behavior for apps that target Android 15.

UIDT is intended to support user initiated use cases such as downloading files from a remote server, uploading files to a remote server or transferring data between two devices via Wi-Fi transport. Since the release of Android 14, the new API has been adopted by a growing number of Android apps running on hundreds of millions of user devices.


What are the benefits if I adopt user-initiated data transfer?

The Android team’s extensive analysis found gaps in foreground services and WorkManager for long duration, user initiated data transfers. Although WorkManager could support retries and constraints, it could not support long duration work which are often necessary for data transfer operations. Developers also found it challenging to use foreground service, which did not provide an ideal user experience during interruption of network connectivity.

JobScheduler’s user initiated data transfer API helps solve for these gaps by offering developers the following benefits:

    • Long duration, immediate background work execution that is not impacted by existing job quotas based on app standby buckets.
    • Helps improve consistency in API behavior across all devices, and the behavior is enforced through Compatibility Test Suite (CTS).
    • Improved reliability of data transfer compared to using a foreground service as indicated by Google Maps own benchmarks.
    • Support for execution when certain constraints are met, such as running only on Wi-Fi or only when the device is charging.
    • Gracefully manages job timeouts and retries.
    • Reduced memory usage and reduced notification clutter when the app is waiting for constraints to be met.

If you’re looking to do short or interruptible background work, WorkManager is still the recommended solution. Check out data transfer background task options to learn more.

“We successfully launched UIDT on Android 14 in early 2024 migrating from our foreground service implementation. After a retroactive analysis on Android 14 vs Android 13 implementation, we now see a 10%+ improvement in download failure rate of offline downloads!”- Matthew Valgenti, Software Engineer at Google

Google Maps successfully launched UIDT and saw improvement in download reliability!

Google Maps decided to use UIDT for their offline maps download use case. This use case ensures that users are able to download offline maps so they have map data even when they lose network connectivity.

What was Google Maps’ main motivation for adopting UIDT?

Google Maps decided to adopt UIDT to ensure that the download service works with the latest Android releases and continues to be reliable and efficient.

“We implemented several features and optimizations, such as resumable downloads so that if a user's internet connection is interrupted or they exit the app before the download is complete, the download resumes from where it left off when the user returns to the app or their connection is restored.” - Emma Li, Software Engineer at Google

What is the trigger point to start UIDT in Google Maps?

The UIDT is triggered when a user decides to download a map region to have that data offline. When a user hits download, the UIDT is triggered immediately and processing of the region begins as soon as possible.

What were Google Maps’ adoption results?

Google Maps rolled out the project using experiment flags to understand metrics impact after each ramp stage.

“We successfully launched UIDT on Android 14 in early 2024 migrating from our foreground service implementation. After a retroactive analysis on Android 14 vs Android 13 implementation, we now see a 10%+ improvement in download failure rate of offline downloads!” - Matthew Valgenti, Software Engineer at Google

How do I get started implementing user initiated data transfer API?

In order to adopt user initiated data transfer, you will need to integrate with the JobScheduler platform API and gate the change to Android 14 or higher.

Check out the following developer documentation to get started with user initiated data transfer:


This blog post is part of our series: Spotlight Week on Android 15, where we provide resources — blog posts, videos, sample code, and more — all designed to help you prepare your apps and take advantage of the latest features in Android 15. You can read more in the overview of Spotlight Week: Android 15, which will be updated throughout the week.

Google Maps improved download reliability by 10% using user initiated data transfer API

Posted by Alice Yuan – Developer Relations Engineer, in collaboration with Software Engineers – Matthew Valgenti and Emma Li – at Google

What is user initiated data transfer?

In Android 14 we introduced user-initiated data transfer jobs, or UIDT. You can use the new API setUserInitiated in JobScheduler to specify that the job is a user-initiated data transfer job. This API is helpful for use cases that require long-duration (>10 minutes), user-initiated transfer of data over network. UIDT is also an alternative API to using a dataSync foreground service, which has new timeout behavior for apps that target Android 15.

UIDT is intended to support user initiated use cases such as downloading files from a remote server, uploading files to a remote server or transferring data between two devices via Wi-Fi transport. Since the release of Android 14, the new API has been adopted by a growing number of Android apps running on hundreds of millions of user devices.


What are the benefits if I adopt user-initiated data transfer?

The Android team’s extensive analysis found gaps in foreground services and WorkManager for long duration, user initiated data transfers. Although WorkManager could support retries and constraints, it could not support long duration work which are often necessary for data transfer operations. Developers also found it challenging to use foreground service, which did not provide an ideal user experience during interruption of network connectivity.

JobScheduler’s user initiated data transfer API helps solve for these gaps by offering developers the following benefits:

    • Long duration, immediate background work execution that is not impacted by existing job quotas based on app standby buckets.
    • Helps improve consistency in API behavior across all devices, and the behavior is enforced through Compatibility Test Suite (CTS).
    • Improved reliability of data transfer compared to using a foreground service as indicated by Google Maps own benchmarks.
    • Support for execution when certain constraints are met, such as running only on Wi-Fi or only when the device is charging.
    • Gracefully manages job timeouts and retries.
    • Reduced memory usage and reduced notification clutter when the app is waiting for constraints to be met.

If you’re looking to do short or interruptible background work, WorkManager is still the recommended solution. Check out data transfer background task options to learn more.

“We successfully launched UIDT on Android 14 in early 2024 migrating from our foreground service implementation. After a retroactive analysis on Android 14 vs Android 13 implementation, we now see a 10%+ improvement in download failure rate of offline downloads!”- Matthew Valgenti, Software Engineer at Google

Google Maps successfully launched UIDT and saw improvement in download reliability!

Google Maps decided to use UIDT for their offline maps download use case. This use case ensures that users are able to download offline maps so they have map data even when they lose network connectivity.

What was Google Maps’ main motivation for adopting UIDT?

Google Maps decided to adopt UIDT to ensure that the download service works with the latest Android releases and continues to be reliable and efficient.

“We implemented several features and optimizations, such as resumable downloads so that if a user's internet connection is interrupted or they exit the app before the download is complete, the download resumes from where it left off when the user returns to the app or their connection is restored.” - Emma Li, Software Engineer at Google

What is the trigger point to start UIDT in Google Maps?

The UIDT is triggered when a user decides to download a map region to have that data offline. When a user hits download, the UIDT is triggered immediately and processing of the region begins as soon as possible.

What were Google Maps’ adoption results?

Google Maps rolled out the project using experiment flags to understand metrics impact after each ramp stage.

“We successfully launched UIDT on Android 14 in early 2024 migrating from our foreground service implementation. After a retroactive analysis on Android 14 vs Android 13 implementation, we now see a 10%+ improvement in download failure rate of offline downloads!” - Matthew Valgenti, Software Engineer at Google

How do I get started implementing user initiated data transfer API?

In order to adopt user initiated data transfer, you will need to integrate with the JobScheduler platform API and gate the change to Android 14 or higher.

Check out the following developer documentation to get started with user initiated data transfer:


This blog post is part of our series: Spotlight Week on Android 15, where we provide resources — blog posts, videos, sample code, and more — all designed to help you prepare your apps and take advantage of the latest features in Android 15. You can read more in the overview of Spotlight Week: Android 15, which will be updated throughout the week.

#WeArePlay | Estante Mágica, the app helping kids publish their own books

Posted by Robbie McLachlan, Developer Marketing

In our latest film for #WeArePlay, which celebrates the people behind apps and games, we meet Robson from Rio de Janeiro, Brazil. As the co-founder of Estante Mágica, he created an app that turns kids into published authors, sparking their imagination and love for reading. Robson's journey from the favelas to creating a platform that inspires millions of young minds is helping to revolutionize education in Brazil. Discover how Estante Mágica is making a lasting impact on education, one story at a time.



What was the inspiration behind Estante Mágica?

It’s a combination of my personal journey and a deep belief in the transformative power of education. Growing up in the Rocinha favela, I saw first-hand how education could change lives — my illiterate grandparents always believed that education was the key to real change, and passed that belief down to me. I wanted to create a tool that nurtures literacy so I teamed up with my friend Pedro to create Estante Mágica.

Estante Mágica, which translates to "Magic Bookshelf," is our way of giving every child the chance to become an author, create something magical that they can be proud of, and to see their own imagination come to life. We designed the app to be a bridge, reaching not just urban schools but also rural and underserved communities, including indigenous villages and areas with fewer resources.

Can you tell us about a moment that showed you the power of Estante Mágica?

Recently, I visited a school in a small village in Rio de Janeiro. The principal apologized for being late to our meeting, explaining that she had just met with a father and mother who wanted to enroll in adult education classes. When she asked them why they wanted to learn to read and write in their 30s and 40s, they told her, "Our son wrote a book here last year, and we don't know how to read it. It's our dream to be able to read the book our son wrote." That moment hit me hard. It was proof that our app isn’t just about helping kids become authors; it's about inspiring entire families to embrace literacy and education.

Founder of Estante Magica, Robson Omelo, taking a photo of a child particiopating on Autograph Day

Tell us about the Autograph Days

These events are held at schools and are all about celebrating the young authors who have created their own books. Each child receives a printed copy of their book, and the day is set up just like a traditional book signing event. The event is not only about the children’s hard work but also a moment of pride for parents and teachers, who see the joy and confidence this experience brings to the kids.

image of the Estante Magica app on a mobile device

What’s next for Estante Mágica?

One major focus is integrating more AI into the app. We want to make it so that when kids create their characters or stories, they can interact with them more dynamically. Imagine a character in a game being able to respond to a child’s questions or comments – that’s the kind of interaction we’re aiming for. We’re keeping an eye on some new features like text-to-video and image-to-video which could add a whole new layer to how kids can bring their stories to life. Ultimately, we’re planning to bring the magic of storytelling to children around the world and expand our platform to more schools, especially in underserved areas.


Discover more global #WeArePlay stories and share your favorites.



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