Starting June 2015, AdWords will no longer support WAP mobile ads for devices without a full-featured browser, including feature phones. At that time, the AdWords API will no longer support creation of new MobileAds or MobileImageAds. Any remaining ads with these types will stop serving and be converted into DeprecatedAds with status REMOVED. These changes will be visible in all supported versions of the API, though the DeprecatedAd.type field may be UNKNOWN until it can be added to the WSDL in a subsequent API release.

Historical performance metrics for any removed ads will still be available for download via the API’s AD_PERFORMANCE_REPORT.

Next steps
To reach the broadest set of mobile users with your campaigns, we recommend that you:

• Recreate your ad in a non-WAP mobile ad format: Once you've created your ad in one of our new mobile-specific formats, you can drive more mobile traffic to your ads by setting mobile-specific bid adjustments. If you'd like to keep a copy of your original WAP mobile ads and their performance metrics, we recommend that you download reports for your original WAP mobile ad groups before June 1, 2015.
• For Display Network-only campaigns: You can create mobile-preferred ads to target specific mobile platforms and mobile carriers for a campaign.

Still have questions? Feel free to visit us on the AdWords API Forum or our Google+ page.

- Adam Ohren, AdWords API Team

Source: Google Ads Developer Blog