I just wanted to give my support to AppGameKit and TGC. I'm not a huge fan of Basic, and was apprehensive of AppGameKit until I saw that Tier 2 allowed you to use the exact same C++ code base on all platforms, something that I am relatively comfortable with. I also wondered how easy/hard the library would be to use. My fears are now gone.
In two days I built a simple client/server based sprite application where more than 2 players can simply open the app which connects to a central server, and move their avatar around the screen with everyone else moving theirs in real time. Now, that's not bad for a Windows application, but to compile it to my Mac, iOS via Simulator AND my Android phone and to see the sprite move around on my phone as I moved them on my Mac and my PC is simply awesome. Compiling can be a bit cumbersome, but once the environments are setup, its easy street.
Thank you guys for taking the time and effort to release this at the price it is at, I can only imagine how tough it was to get all the platforms covered. I will now dig deeper and make the game I have been planning and I cannot wait for Version 2.