Where there is a will, there is a way... Someone will always try to game your system in an effort to automate or win as much as possible.
Take flappy bird, probably not a good idea, there's already a few flappy game beaters out there, check out Hackday for an example:
http://hackaday.com/2014/07/27/an-automated-flappy-bird-player/You're going to want to put in something that is difficult to game against with a camera, an fpga board, and someone with way too much time on their hands.
My suggestion to bit-lottery for example was to using something from the blockchain as part of his game, you may want to consider something unique to keep people from autoplaying your games to win with an element of randomness at a gameplay level not determine by pixel collisions, etc.
