I have purchased an HTC Incredible and have dived into the world of android! Only to find myself totally confused about the API levels and backward compatibility.

My device runs the 2.1 OS, but I know that most of the devices out there run 1.5 or 1.6; and soon the 2.2 OS will be running on new devices. The SDK has gone through such enormous changes, that even constants have been renamed (from VIEW_ACTION to ACTION_VIEW for example). Methods have been added and removed (onPause replacing the earlier call, etc al).

So, If I want to write an application that will work from 1.6+, does that mean I have to install and write my code using the 1.6 API; then test on later versions? Or can I write using the 2.1 SDK and just set the minSDK level and not use "new" features?

I have never worked with an SDK that changes SO drastically from release to release! So I am not sure what to do....

I read through an article on the Android Development site(and this posting on stack overflow that references it: http://stackoverflow.com/questions/2076150/should-a-legacy-android-application-be-rebuilt-using-sdk-2-1), but it was still not very clear to me. Any help would be appreciated