iOS? Yes load times are quite long, on my oldest player I did finally delete and the reinstall the app because I had an almost 5GB dataset. Once nuked I'm down to a couple hundred mb and got back the space. Loading isn't that much faster.
As for crashing, notice this is a big problem on older devices such as 1st gen iPads and 4th gen or older iPods. They crash as soon as I attack the raid boss so only fix is to link to a faster device if you have it or can. Still haven't tested the link other device feature but hopefully today.