I am using a HTC Wildfire loaded with Android 2.2.1(Froyo).
Froyo has the Android API 8, and looking at the 'Developer guide' on Android website, tells you that there has been a considerable change from API 8 onwards. This means that any app which I make, will be tested for hardware containing Android version 2.2.1 and above.
Looks like I started programming for Android at the right time :)
