John,
I use two Android tablets for DCS. Both were loaded with the app from Google Play Store. When I upgraded the app the second tablet was automatically updated with no additional cost. I actually had the app on my Android phone for a while but did not use it or need it there. There has to be a way to install the app on your devices. There were two premium costs involved - one for $25 and the second for $5 to have all the functionality. HTH
Buzz