The mobile version of hearthstone had a lot of problems lately, but in an upcoming update (in the next couple of weeks) the problem should be fixed.
How it may look:
I wanted to give everyone an update on the state of mobile, as we’ve seen quite a lot of threads about it.
In our next major update we will be rolling out a fix that should address the majority (if not all) of the crashes on mobile. This update will be rolling out in the next couple of weeks. Sincere apologies for the poor experience, we’re working to get things back on track.
The team is continuing to pinpoint what other issues may exist and are hoping to squash these pesky bugs in their tracks.