I have been seeing this the last few days on both my tablet and phone. Both Android 4.4. Never had issues and until just now it has never crashed when I started a match, like it just did. I know people were having issues a lil bit ago but didn’t know it was back.
I have seen it couple of times on my phone in the last week (Android 5). The worse thing is that I had started a match and the crash caused me to lose the match and my heroes to lose a substantial amount of hit points 
I’ve had a lot of crashes lately. Never did before. Game restarts all the time as I navigate from tab to tab or go into one. Haven’t had it happen mid-game yet, but it’s definitely a new behavior and not of the good.
Happened twice to me today. Just after starting the match in ddq for the legendary token. Costed me a quite a lot of boosts, so i have only one more chance at beating this level with boosts (without is impossible for me)
True for me too, happening several times a day now.
403 days played and I’ve never had crash issues… Until this week
I’ve had crashes while selecting my team, immediately upon entering a match, while making my first move, mid
HTC1 m7
Android 5.0.2
I play only on my galaxy note and experience crashes several times weekly to this day. They always occur right when I start a match. Repeat - all crashes I experience occur at the start of matches - never during an ongoing match, and never during toggling between events, upgrading, selling, buying. Predictably, when I reload the game, the 3 characters I was playing with are injured as if I lost the match where the crash occured and the buffs I used are gone. In the case of a PVE event ( be it SHIELD simulator, PVE tournament event or lightning round ) in addition to the aforementioned, the match up selected where the crash happened is gone.