title: How can you make a review copy of an Android app?
body: <p>I've been asked for some review copies of an Android app I've written, which is great, but I'm not willing to give out the full app to just anyone.  I want to make a time-limited version (which works for about two weeks, then gives up the ghost).</p>
  
  <p>What is the easiest way to do this?  I haven't tested this myself, but I think that in theory if one built the app using a keystore which expires in two weeks might work.  Is that correct, or do I have to put a line of code in the app which shuts it down if you attempt to boot it after a set date?</p>