Already on iOS 7? We discovered a small issue on Venice tides with the new iOS.
The picker to change your personal 'acqua alta' level is not working anymore. Well, actually, it is working, but it disappeared :P If you try to move your fingers on the screen you can hear the click click sound of the picker and see the value changing on top. So, the picker is there, but it's invisible!
Don't worry, we're working on it. We plan to release an updated version in a couple of days.
Btw, we've googled the problem but it seems we're the only one having it. We'll let you know how we solved it, in case there's someone out there that needs help with the same issue :)