Earlier quoted context omitted.
He/she probably can't. The concept is not new. Here's a flash version of the same game. it is a few years old. [1]: http://www.addictinggames.com/puzzle-games/3dlogic2.jsp
Who says you need completely novel gameplay mechanics to charge money for an app? Surely more polish, hand-built levels and an app are sufficient. Whether OP would make more on ads or IAP remains to be seen, though. An IAP to get more levels would be a good way to hook users.
Free sells.