"Much like the way distributed computing projects like SETI@home or Folding@home work by using the idle processor cycles of your computer to contribute to crunching numbers in a massive swarm, the Icominer mines bitcoins to funnel into the developer's wallet. The main difference here, however, is you're actively opting in to downloading and installing SETI@home or Folding@home, versus having your battery drained to mine bitcoins for someone else on your iPhone".
Free to Play Takes an Evil Turn: Passively Using Your Phone to Mine Bitcoins for Developers | Touch Arcade