Xperia Z3 :: Applications Can't Open?

I recently got my Z3+ a few weeks back and it has been working well for me ever since. A few things i've noticed is the phone tends to overheat when its put underwater, and loses network coverage underwater as well. A rumour i've heard is also that the water-resistant feature of the phone is not compatible with salt water? Lastly, only problem i'm having is with applications. Applications i've downloaded, mostly games, tend to give the "Unfortunately, _____ has stopped working." message.