Booster and fly out

Spinnifix

Yesterday I took a booster extra in the game that was supposed to make playing easier and thus I could have finished. Unfortunately I flew out of the app while playing. Which happened to me often. On the one hand booster are offered and then you fly out. What shoud that? Is this all intended here? Can you please get that so that you can play to the end? Otherwise you would not need a booster.