title: produce free *.apk file from android studio 1.1.0
body: <p>i have developed an app from android studio 1.1.0 and. it work fine with my android studio emulator. now how to generate an *.apk file from the project. it was very easy in eclips. apk was automatically generated.</p>
  
  <p>NOTE: i don't have any signature . i want to develop an free app without anyting to buy. example signature,license and all. </p>