Water Lock arrived with Apple Watch Series 2, the first model built for swimming. It does two jobs. While it is on, the touchscreen ignores input so that water does not tap things for you. When you turn it off, the watch plays a short series of tones that push water out of the speaker. That second part is where the idea of "water eject" for phones came from.
How the ejection works
The speaker is the one opening on the watch that cannot be fully sealed, because sound needs air to travel. Apple's answer was to let water in and then use the speaker itself to throw it back out. The watch plays a low tone that makes the speaker vibrate strongly, and you can often see small drops leave the slot on the side of the case and feel the buzz on your wrist.
How to turn Water Lock on
- Press the side button to open Control Centre. On older versions of watchOS, swipe up from the bottom of the watch face.
- Tap the water drop icon.
A drop appears at the top of the watch face to show the screen is locked. Water Lock also switches on by itself when you start a water workout such as Pool Swim or Open Water Swim.
How to turn it off and eject the water
On watchOS 9 and later, press and hold the Digital Crown until the display says "Unlocked". On earlier versions, turn the Digital Crown until the circle fills. Either way the watch then plays its tones and clears the speaker.
If the speaker still sounds muffled
- Run it again. Turn Water Lock on and off two or three more times. Each cycle ejects a little more.
- Rinse after salt or chlorine. Apple recommends rinsing the watch in fresh warm water after swimming in the sea or a pool. Salt left to dry in the speaker crystallises and blocks it.
- Let it dry. Leave the watch speaker-side down overnight. Apple notes that barometric altitude readings can also be off until the water has evaporated.
- Do not insert anything into the speaker or microphone openings, and do not shake the watch hard.
What the watch can and cannot handle
Apple Watch Series 2 and later are rated water resistant to 50 metres, which covers swimming in a pool or the sea. Apple Watch Ultra is rated to 100 metres and supports recreational diving to 40 metres. The first-generation watch and Series 1 are splash resistant only and should not be submerged.
Apple advises against wearing any model in a sauna or steam room, and against exposing it to soap, shampoo, perfume or lotions, because these wear down the seals. Water resistance is not permanent and cannot be re-tested or resealed.
Why iPhone does not have it
There is no Water Lock on iPhone. The phone's speakers sit behind the same kind of mesh and trap water the same way, but Apple has not added an eject tone to iOS. You have two ways to get the same effect:
- Open the iPhone water eject tool in Safari and tap the button.
- Add a Water Eject shortcut to the Shortcuts app so you can trigger it with Siri.
Both play a low, pulsing tone through the phone's speaker, which is the same principle the watch uses.