title: Keep android app in foreground unless in in settings
body: <p>I have an app for a customer (refer to it as "their" app). When "their" app is open they do not want users of the device to use any other apps. 
  The only way they want to get round this, is if i create a login page within the app, and from there you can go to the android settings page.  If the android settings are accessed, then the user should be able to go anywhere they want, until "their" app is in the foreground again, then the device should be locked into using just that app.</p>
  
  <p>If this makes any difference, "their" app is a cordova app.  I dont think it will, but thought i would mention it anyway.  Needs to work in android 5.0</p>
  
  <p>Is this possible at all?  What would i need to implement for this?  A service and timer?</p>
  
  <p><strong>UPDATE</strong>
  It is a tablet, so it will never ring.
  If the user presses the Home button, nothing should happen as the app should stay in the foreground</p>