It's the standard mobile stuff. Casuals come and go with the winds. What matters for these games is how many cash whales they can get, but the same truth holds for every F2P app or online game. Hardcores can't play everything at once. So, naturally there is only so many titles that can be sucessful in the long term.
This is the reason why the mobile and online space is full of failures. Will pokemon go be one of them? No idea.







