(4.7/5) Exponential Invasion is an extremely simple and unique strategy game. You must combine numbers to add them together, in order to destroy "towers" (blue numbers). Your attacking number must be larger than the tower in order to destroy it. The graphics are extremely simple and minimalistic, with easy-to-navigate menus and simple level design. There is music, but it is turned off by default. The music, which is jazz, is the same throughout the game. I found the game to lose a lot of it's appeal with no background music. The game's controls are simple, just like the rest of the game. You just have to tap to select a number, and tap where you want it to move. There's not much else to say about Exponential Invasion. The game is pricey, it costs $2.99 on the app store, but it's a good simple strategy game.