For this latest war (server14), I made an attack on a weakened defender. When I had claimed victory, I received an alarm notification from my phone’s clock that took me out of the game during the victory poses. I took care of the notice in a few seconds, but when I re-entered the game, it loaded from the title screen. When I checked the war again, the opponent I thought I had defeated was still being attacked. Checking the war logs, my attack wasn’t listed; however, I was prevented from making any other attacks without an extra attack use. Eventually the phantom attack disappeared with someone else claiming the win, no record of any attack from me, and still needing to use an extra attack to compete. Suffice it to say I’m more than a little miffed.
Man, that sucks… unfortunately, I don’t think there is any way around that except to wait until the victory stuff is fully out of the way before leaving the game. I just wish the game would run longer in the background before having to restart upon reentering the game.
I would think they probably figured that out at some point in the last 22 days 
To me, this glitch is consequential for trying to win a guild war. Here’s what I usually do: if there’s something impending, I would just restart the game and come back to it. Didn’t do this one time, and for several minutes, the game crashes during a guild war, and I see the other team “under attack”, when I’m not doing anything(nor the other guild members). When this happened, I was afraid that we(our guild) will lose a current guild war, just because of this glitch.
I actually haven’t had to deal with crashes since I switched to a newer phone. But before that— OY— did it SUCK! Coliseum and guild wars were basically unplayable for me. Crashes in Heist would occasionally happen and the thief would consequently steal a valuable. So glad that nightmare is over.