Even if your phone has an Ingress Protection water-resistance certification, leaving it next to a pool may not be such a great idea. Water-resistant seals can wear down over time, creating vulnerabilities that are impossible to detect. But a new Android app that claims to test your phone’s water resistance without using any water may offer some peace of mind.
Developed by Ray M, the Water Resistance Tester uses your phone’s built-in barometric sensor to check if it’s properly shielded from the elements. The app prompts you to press down on your phone’s display with two thumbs, which can create minor differences in barometric pressure.
Properly sealed phones are airtight, so when force is applied to their screen, their internal pressure will increase. But phones without Ingress Protection are not airtight. Pressing against their screen forces air out of their body, leaving barometric pressure practically unchanged.
Testing the app with an IP-certified phone and a device without water-resistance shows that it is pretty accurate. And when you remove the SIM card tray from a water-resistant phone, the Water Resistance Tester will recognize that the device is exposed to the elements.
Still, you shouldn’t put all your trust in this test. Taking your phone for a swim is never a good idea—if you’re lucky, it will only damage the microphone and speaker. If anything, this test is just for peace of mind, or for confirming whether your phone has built-in water resistance. You could also use this test to find out if your phone has been repaired in the past—taking a display off a phone permanently compromises its airtight seal.