To clear the air on some of the previous posts in this thread;

1. Make sure you set your power settings on your phone to allow the app to run in the background
2. It takes about an hour or more to start showing some earnings.
3. The app is meant to run in the background. It benchmarks your hashrate then airdrops accordingly. I have found if you keep it open and dont minimize it then yes, your phone gets a little bit hot. Keep it minimized
4. The price needs to pump for the earnings to be something to really get excited over, but still for an app in the background its a good deal.
5. When leaving it running in the background I have not noticed any change in my battery life.

Also remember
This is simulated mining, this is basically just an airdrop