App performs inconsistantly...how to check for memory leaks?

I (was!) almost done with an app to submit to the app store but when I tested the final build on my iPad it started performing strangely.

It had never done this before, but it's crashing almost CONSTANTLY. Every few seconds or so. I haven't changed much of anything since the last time I tested it and I can't really figure out what would cause it to crash so much.

From the menu you can choose a button to go to other frames in the main timeline. Half of those work, half of them make the app crash. This is new and I think I might have a memory leak somewhere because it's consistently inconsistent.

At first I thought I had a stack overflow somewhere; however, testing in mobile debug mode doesn't cause any errors or even warning output messages - nothing. It runs just fine.

So is it possible that the problem is stemming from hardware? I can't imagine this app would be using up too much memory - it is full of vectors, but there's nothing more complicated than touch and drag because it's just a puzzle.

How would I test something like this if debug mode isn't throwing any exceptions?