Xenowerk is a twin stick shooter that costs $1.99 and includes in app purchases that range from $0.99 - $3.37 per item.
Con Demanding game
Due to the high polish of the game the graphics can be demanding, in order to get the smoothest gameplay it is recommended to close all apps when playing. Higher end hardware will also obviously perform better. So sadly lower end phones will most likely not play this game very well.