S8, please add a "do you want to use gems to purchase xyz". This game lags, restarts, doesn't react so much that many players inadvertently speed up collection times because we think our choice didn't register, then before you know it, you've spent gems on something as inane as a cow collection.
I, personally, won't purchase any gems until this is added.
(Someone suggested I close out my game, I do that every time. I also restart my iPad practically everyday)