The latest version of Double Star, an Android space war app, allows you to set game difficulty on the Settings screen. In the EASY game, there are fewer alien starships, and the enemy are less aggressive. A few people had commented that the game was perhaps too difficult. The EASY setting should help.
To download the beta version of the app, visit the Double Star community on Google+, here is the link: https://plus.google.com/u/0/communities/113741436953313178716.
The full game experience includes: (1) training at the academy; (2) saving our planet from the alien invasion; (3) searching the galaxy for the enemy home world. Twenty levels are available for play. There are mysteries, challenges, and rewards along the way.