No one has a guaranteed way to make more money quickly...but here's some ideas.

Invest in startups - You might see amazing returns in ~2-5 years, but the risk is very high.

High risk hedgefunds - All equity/bond/commodity investment doesn't have to be slow. It can be risky and full of high returns/loses.

My favorite idea... Expand what you're doing: Use your proven track record and revenues to bank roll your own app store based startup/shop. Hire some people, branch out a bit and look into the android platform. You can avoid the need to take money from outside investors, and multiply your money that way.