I've checked it out a bit and I like it.
It's not nearly as easy to deploy it with Android or iOS, but you can use lua to script and lua is very similar to AppGameKit basic in syntax. However lua is extremely powerful.
You would need to set up Android java/eclipse projects from scratch. Which means you'll have to build your own C++ functions to call your java code stuff like IAP, Facebook, etc.
It's used by a lot of major studios so... it is good
Also there are a ton of tutorials on how to set things up like FB integration and once you get the hang of NDK+java I think it won't be too hard. I'm still trying to get the hang of it for AGK.