This is from the ADB debug console:
03-19 09:47:53.706: I/Unity(15424): NullReferenceException: Object reference not set to an instance of an object
03-19 09:47:53.706: I/Unity(15424): at UITweener.Update () [0x00000] in <filename unknown>:0
How do I even begin to debug this? The issue isn't present on PC.
Edit: There certainly doesn't seem to be a way around this. Other tweens seem to work, I can't begin to understand why this wouldn't. It's not the only tween I have assigned to a UILabel either. I'm just going to have to remove it and perhaps find another solution.