I've found myself working in iOS again for the past few days for the first time in over a month. Every time I go back to it after a long hiatus I discover just how much Objective-C I've forgotten since the last time.
We're just about ready to submit our app to the store and I'm moving on to an entirely unrelated set of projects for the next couple of months, so I don't know when I'll be getting back to iOS development again. I'm sure I'll go through the adjustment pains then too, but here are a couple things I'm sure I won't forget:
It's not the syntax that's challenging, StackOverflow is a lifesaver, it's thinking about the code in a very different way. (The first day back in Objective-C involves a lot of profanity.)
You can't even open the Storyboard without committing a change and Git conflict resolution is a major pain. (Yields more profanity.)
Writing delegates is a process, which is probably why I've really come to appreciate NSNotificationCenter for basic events between views.