This app will help you test whether the IP67/IP68 water resistance seals on your phone are still intact by using the barometer built in to your phone. Do note that the seals can become compromised with drops and device aging - keep your phone away from all liquids!
Note: If your phone does not have a built-in barometer, it cannot be supported. Having a barometer built-in to the phone is required for the core functionality of this app, and no app can install physically missing hardware.