I'm sure AppGameKit would like to make this available for everyone, but the problem is that Apple only allows you to register 100 devices as test devices. This is a very limiting issue that I have a tough time with myself. We used quite a few when testing Wordspionage and unfortunately not everyone who signed up for beta actually ever participated, so we lost those place in our count of allowable registered devices.
Your best option is to register as an iOS developer and set up your device as a testing device. The guides that Apple f=provides for this are reasonably well-written and we can help you if you get stuck.
You can also run your game in the simulators to test basic functionality, pretty much everything works in the simulator, but you'll have a significantly reduced framerate. I've found that iOS devices seem to have pretty good framerates, so there's not much to worry about. If your game runs on an Android 2.3 device that is a little old then it will run on an Apple device. If you scour this thread you'll see posts by me about some of the potential issues you might face. All-in-all they're not too bad.
If you plan to release a game on iOS in the next year then I'd really encourage you to purchase a developer's license. Working with iTunes connect is a bear and you're going to want to become familiar with it sooner rather than later.
A final note: You must have a Mac to develop for iOS. It's a bit unfortunate, but you need one. I bought a Mac Mini off of ebay for about $500USD. It's perfect for a development computer.
