title: Compatibility of Android applications among different versions of Android
body: <p>I created an Application about 1 year back on Android version 2.1 and made available to all the other versions of Android. At that time Android mobiles with versions 2.1, 2.2 and 2.3 were very common.</p>
  
  <p>So I tested my application on all available versions and there was no issue.</p>
  
  <p>Now Android with versions 4 has become the hottest mobile in the market. When I test my application on the versions of 4 it started crashing.</p>
  
  <p>My question is how to ensure that the application that we develop now should be compatible with the later versions which are not available now ?</p>
  
  <p>How to write applications [OR] what are the things that I need to consider so that with minimal code changes it should work on all the versions ?</p>