Wow...I'm surprised at how few threads (and thus designers) there are here...
I wanted to know...I'm trying to design an interface design for an app for a client (probably non-paid but that's another rant) and its a fitness-based app.
Questions are:
1) In general, how close to I need to stay to the standard Apple "look"? I've read they prefer you don't stray too far from it as users expect to know what to do when they open an app.
2) If I do make changes in this type of app design (a tool/productivity app), how different can the graphics really be? It's not like a game where you can go kind of crazy. It's something that you look at and use for interval training--timing your sets--so I'd think it shouldn't be very fancy.
I've never done this before so I have to do all this research in addition to the design.
Any thoughts on how I should approach the design?
Really it can be as different as you want! Just try to follow the basic structure. And, if you come up with something really beautiful and unique, Apple will definitely appreciate it.
There are plenty of apps on the app store that use their own totally unique UI. Some crappy, some great. Apple is pretty lax in this respect in terms of app approval, as long as it isn't confusing and totally backwards.
Then again there are some super confusing apps on the app store, even pretty successful ones.