title: Require only monthly web authentication of android app
body: <p>I want to distribute my app in a private appstore. I have read all the good advice here on how to integrate web authentication. Thanks everyone.</p>
  
  <p>But I dont want the user to seek authentication everytime they use an app (they ll give up soon). Instead, I want to require authentication maybe every 30 days.</p>
  
  <p>Is there a way to save an authentication token received from the web server on the app/device such that it will permit use of the app for a 30 day period? Please bear in the mind that the app is not expected to be running always.</p>
  
  <p>Thanks </p>