This is an augmented reality game developed with libgdx and scala. You must have a gyroscope on your smartphone. The aim is to kill the spiders dropping down, as well as stop the spiders making alien webs. You can get closer to the spiders by holding the bottom of the screen and walking. To fire press anywhere else apart from the bottom of the screen. The spiders will always keep coming.
The walking is simply implemented by checking vibrations of the phone and assuming if you hold the bottom of the screen then you are moving in the real world.