Why do you call it mining? Its is not profitable to mine a coin through your phone. The power your phone can generate won't generate any significant earning for you. I think the project you are talking about where you are suppose to mine those coins are actually collecting them. Project team is distributing them for free through game and something that they claim to work as mining. This is a way to attract a large group of people who will actively use their application for a small rewards. These project are just some short term hype.