Google is getting tougher on misusing apps as Android app developers that use Accessibility Services for reasons other than helping users with disabilities must switch to other methods or the apps will end up dropped from Google Play.
Google did not reveal why they are making this move, but it appears to be a move to slow malware developers.
Accessibility Services are meant to help users with disabilities use their device, and therefore have full access to the contents of interfaces.
While that is a good thing, they can also end up misused to activate device administrator rights and set itself as the default Home application, interact with the graphic interface and intercept the information entered by the victim, lay windows over other windows and apps running on the device.
Adware makers led the pack in abusing the service, and malware authors began doing the same after the majority of Android users switched to Android 5.0 (Lollipop) and later. Before Lollipop, they were using the getRunningTasks() API to steal information, but Google made it impossible for third-party apps to use it.
The Google Play Review Team started emailing app developers telling them about the change.
This change might be a big problem for developers whose apps rely on using android.permission.BIND_ACCESSIBILITY_SERVICE to provide easy functionality.