Sorry for wasting your time if someone already suggested this
An Idea for KR
The levels in KR are always limited by the screen but why not make it that they are larger. To move drag your finger or curser on to the edge of the screen and the screen will move that way.
Maybe a minimap?
It would improve gameplay and make it harder since you can't see the whole map and it would be much harder to manage your towers and multiple lanes
Just a suggestion