Originally Posted by Kev1000000
Well, it depends how sensitive it is. If its like most cell phone stickers, then putting it where it can easily be subjected to humidity is a really bad move.
Condensation forming from being in a dry cooled environment and going to a hot humid environment is more likely to happen internally around the battery than it is in the headphone jack which is open to the air, and will warm up and dry out faster than the internals.
If this is the case, then the water detection spot is actually a good idea.