Very Very fun game, Loved playing it.
The requirement of consistently having to tap on the screen gets tiring fast. you could have maybe integrated some sort of machin gun mechanism and the player has to keep his finger on the screen and the gun just keeps shooting and also at the same time receiving which direction to shoot
Yeah the level of difficulty goes from like 0 to 100 in .6 seconds
And also not getting the diabolical part of the game