如何使Android 2.2应用程序在2.1中工作

Hi I made an android app with 2.2 selected and API 8 Now how can I make it work in 2.1? Is it possible to give support for 2.1 devices? Or I have to develop all the app again from scratch? :-( Hope not Please kindly help me out Thanking You ChinniKrishna KothapalliHi I made an android app with 2.2 selected and