I believe the mega adk is able to interface with this: http://handbagdevices.com/
This is a really simple way to interface arduino with an android without having to write a line on android code.
There are tons of tutorials on using handbag as well such as
http://rancidbacon.com/p/android-arduino-handbag/
http://www.freetronics.com/blogs/news/4617352-using-handbag-with-the-usbdroid-and-android#.UXyQkpNplzA   (this one uses a usbdroid                                                                                                                                                                          but it should be the same)

Hope this helps
-Luke

Sorry, maybe I miss something, but where are "tons of tutorials", as you marked here? Can't find more than two. Thanks for your reply.

Well, pity that such great application is without any answer.
Installed, tested and great results. Congrats.

I am skip app ratting on Google Play, they pushed me to link with Google+, which I don't want at the moment.

Sorry for my language, not native.