Cloud Backup does not work.
I just reinstalled, and lost my progress, so I can’t remember all the specifics, but my (beta) review covered most of what I have found broken so far.
Deckhands still cannot be leveled beyond 1009 without causing a major malfunction. If you level Diego to 1010, after the next restart, all the deckhands will be listed as n/a and will no longer be able to upgrade or level up. (Tip: Breathe deckhands starting with Seawitch, and keep leveling as long as you can before the game resets. When you have to reopen, only Seawitch will be broken, so you can level the next deckhand down ’till it resets, then the next, etc. Got up to 360+ that way one time).
Some powers don’t work. One increases treasure box odds (useless waste of mana), another promises upgrade discounts–and everything changes color earlier–but nothing can be bought until the full original purchase price is attained. I’m sure there are other examples.