Last week, I got my first Android phone: A Wiko Cink King! It's not a Samsung, it's not an Apple, but it's definitely worth the 200 EUR it cost me. And since I now have an Android device, I can develop my own apps, and my first implementation had to be related to ray-tracing in some way. Let's be honest, interactive ray-tracing on a 200 EUR device... the dual-core 1GHz CPU simply cannot handle it. But there is another solution: Why not use the GTX 480 sitting in my desktop box remotely? And since I already have an HTTP GPU server in stock, writing the mobile app making HTTP REST calls did not take more that a few hours, using the really cool Android Development Kit.
Sample code for the GPU HTTP server: https://github.com/cudaopencl/GPUHTTPServer
Android SDK: http://developer.android.com/sdk/index.html
APK downloadable from github, but since this needs a GPU server, email-me for a demo!