It’s not magic, it’s science. The sound is carefully engineered to create air movement strong enough to push drops of liquid out of the speaker, which is also how the Apple Watch’s water ejection feature works. The edge and iFixit were a bit skeptical about how well a third-party audio that wasn’t specifically tuned to different phones would work, so they tested it on four phones: an iPhone 13, a Pixel 7 Pro, a Pixel 3, and a Nokia 7.1.

The phones were first submerged in a UV bath for about a minute, after which they were tapped to expel some water, and then a video was played of water being expelled. The phones were left out overnight before being checked to see where there was any residue of the UV dye left, to find out where there was still liquid.

The results were mixed. Pixel 7 Pro was completely dry, the Nokia 7.1 barely survived, and “the iPhone13 and Pixel 3 were somewhere in between.”

The squad also took a close-up video of each phone’s speaker and showed them draining liquid. In short, the video works, but not necessarily perfectly. While it can remove the drips around the speaker, it has no effect on other break-in points like the USB port and SIM card slot.

And no matter how perfectly the video transmission works for you, it is better not to take your phone into the shower or have it with you when you do the dishes, as the watertightness of a phone can deteriorate over time.