I’m on an Android device (Server 23, approx 11:00) and this game has been consistently crashing throughout the morning. This doesn’t happen in any particular mode, or transition, but just happens randomly after several minutes into the game.
So far I’ve had it crash on me: post battle, checking daily quests, and upgrading heroes.
I’ve never experienced crashing in this game whatsoever in almost 3 years of playing.