Fixed spawning issues

Discovered that the app was not spawning the vast majority of enemy ships on my friends' phones. Tracked it down to issues with Proguard (in AndroidStudio debugging apps are built without Proguard). Instead of chasing down the Proguard error, I just disabled it (since all the source files are here anyways).

Also made interstitial ads appear every 6 levels or so.

More complex enemies and improved movement

Reduced movement sensitivity and increased the different types of guns some enemies can use.

First update

Redesigned store
Increased frame rate
Improved movement controls
Player must survive each level for a certain amount of time, instead of a certain amount of score
Advanced enemies begin spawning earlier in the game. It's more difficult now!
And more!

Initial publish on play store

1.0

balancing score needed to end level for a more interesting/less monot…