Step 10: Hacking the Code
I got a lot of help from some really great examples (and got really thrown off by some bad ones). You can look through my code, or browse some of these great samples yourself:
Arduino ADK Firmware
This was incredibly helpful for getting started with the ADK, as the "official" example code only worked if you had a very specific setup on your board. This serves as a much better "Hello World" for working with the ADK.
ADK Android Example
This is the official example that Google released. You can hack it up and get it to do what you want!
Using Foursquare with Android
This guy is great and even answers your questions about his code!
GPS and Android
Nice simple way to access your GPS coordinates