While iOS is known for making strides in accessibility from the very beginning, Google’s Android platform is also taking accessibility very seriously for its users. For Android app developers, there are many options for building accessibility into their apps such as text-to-speech, haptic feedback, gesture navigation, trackball and directional-pad navigation.
Android developers can also build their own accessibility features into their apps above and beyond what the core OS offers. Google has provided an online resource guide for building accessibility into apps, including Making Applications Accessible, an Accessibility Developer Checklist, and Building Accessibility Services.
Below is a video from Google I/O 2012 discussing Android accessibility.