this example code could be find on following url
https://github.com/emacslisp/XNA2DGame/tree/dev/Android/PlatformReading
1. How to build apk from visual studio
<1> change build mode from ‘debug’ to ‘release’
<2> select project properties and change option on ‘Application’, ‘Android Manifest’, ‘Android Options’
2. How to debug android with xamarin C# code
debug on physical device is the best way to go, simulator is very slow.
choose device and press F5