Whenever you find that your app is slow or choppy, there's a good chance that something in your code is taking longer than it should, especially if your memory usage appears to be within reasonable range. For instance, if your app uses less than 50 MB, memory is not likely to be an issue for your app, so seeking the problem in your code's performance makes a lot of sense.
To discover where your code is lacking in the performance department, it's a great idea to profile your app in Instruments, by either selecting Product | Profile in Xcode's toolbar or by pressing Cmd + I. To figure out what the code is doing, you need to select the Time Profiler template when Instruments asks you which template you want to use. This ...
