title: Should I replace Android Activities by Fragments?
body: <p>I have a large Android game in which there is an Activity for each logical screen.
  (Splash screen, start screen, level chooser, game screen and Settings are distinct Activities).
  Everything is working fine right now.</p>
  
  <p>If I rewrite everything so that there is only one activity and the logical screens are Fragments, Will it reduce RAM or CPU consumption?</p>