title: Complex activity issues
body: <p>I think my problem is because I'm misusing inheritance. I've got 4 activities, all extend BaseActivity which shares common code (onClick, onItemClick, static and non-static methods). Each activity get it's data from web - that includes images. When I use whole app for longer period of time I've got memory leak errors (VM won't let us allocate xxx bytes) and app crushes. </p>
  
  <p>If I properly understand - it's because by extending these 4 activities I make them something like inner classes of Base Activity - that's why their onDestroy() methods aren't invoked when I switch between them. Moreover - GC don't reclaim any RAM and heap is beeing clogged. BaseActivity is holding all the data (for example images) thus allowing showing them when Back button is clicked with no need to recreating the data. </p>
  
  <p>If that's true - another option is make them seperate by using helper classes to share common code - but then, when I will be switching between activities - they will be downloading it's data over and over.  </p>
  
  <p>I'm I right and is there any solution ?</p>