Apple Watch Ultra Depth App: How to Use It

The Depth app on Apple Watch Ultra shows your current depth, elapsed time underwater, water temperature and maximum depth during a recreational water activity. You can open it before entering the water or let it start automatically when the watch is submerged; first check the watch’s fit, battery and water-related safety guidance.

What You’ll Need

An Apple Watch Ultra or Ultra 2 with the Depth app available.
A secure, comfortable watch fit; the band should keep the watch in contact with your wrist during the activity.
A charged watch. For an activity that may run close to the app’s 40-metre depth limit, plan to stay well within that limit.
For scuba diving, a suitable dive computer and training. Depth is not a substitute for dive planning or a certified dive computer.

Step-by-Step

Know what the app is for. Depth is designed to display basic information for recreational underwater activities, such as snorkeling, swimming and shallow freediving. It records a session’s elapsed time and maximum depth, but it does not provide decompression information, tank pressure, dive plans or warnings for every hazard. Do not treat it as a complete dive computer.
Check the watch before you enter the water. Make sure the watch is secure and the screen is in good condition. Check that the battery has enough charge for the whole outing, including time before and after the water. Apple advises against using Apple Watch Ultra for diving below 40 metres (about 130 feet), and the Depth app is not intended for dives at that depth or beyond.
Choose how to start the session. To start manually, press the Digital Crown to open the app list or app grid, then tap Depth. If the app opens to a start screen, tap Start. You can also allow Depth to open automatically when the watch is submerged. The automatic behavior can depend on your settings and the water activity.
Review the display as you descend. The screen shows your current depth and the time elapsed in the water. It also displays water temperature and the deepest point reached during that session. Depth is measured from the water’s surface, so the reading may change as you move up or down. Read the information without letting the watch distract you from your surroundings, breathing, buddy or planned limits.
Keep the activity within the app’s intended use. The Depth app can be useful for checking basic depth and time during shallow water activities. It does not tell you whether it is safe to descend, how long to stay at a depth, or when you can safely fly after diving. Follow your training, established dive procedures and any guidance from your dive professional. For scuba, use appropriate dive equipment, including a dedicated dive computer.
End the session when you leave the water. If Depth is running, follow the on-screen controls to end the session; on some versions or activity flows, it may finish automatically when the watch leaves the water. Confirm that the display is no longer showing an active session. After the activity, rinse the watch with fresh water if it has been exposed to salt water or pool chemicals, then dry it with a lint-free cloth.
Review the session. The app may show a summary with the session’s maximum depth and elapsed time. Use it as a basic record, not as a replacement for a complete dive log or the information required for dive planning. If you need a detailed record, keep one using the method recommended by your instructor or diving organization.

Common Mistakes

Assuming Depth is a dive computer: It does not calculate decompression stops, remaining air or no-decompression limits. Use a proper dive computer for scuba diving.
Going beyond the app’s depth limit: Do not use it for diving below 40 metres (about 130 feet). Staying within the limit does not by itself make a dive safe.
Expecting automatic launch every time: The app may not open as expected if automatic launch is disabled, the watch is not submerged as anticipated, or the relevant settings differ. Learn how to open it manually before entering the water.
Reading a session summary as a safety clearance: A recorded depth and time do not establish that a dive was safe or that it is safe to fly afterward.
Using the watch for water sports outside its rating: Water resistance can change over time, and damage can affect it. Avoid activities or depths outside Apple’s stated guidance for the specific watch model.

Tips

Open Depth on land before an activity so you know where it is and can check that it launches.
Use the watch’s Action button for a convenient shortcut if you have assigned it to Depth in the watch settings. Verify the assignment before relying on it.
Keep the display readable and avoid unnecessary interactions underwater. If Water Lock is active, turn the Digital Crown as prompted after leaving the water to clear water from the speaker.
Rinse and dry the watch after salt water or pool exposure. Do not use compressed air, heat or sharp objects to clear water or debris.
Check Apple’s current guidance for your exact model and software before an important water activity; settings and supported features can vary.

Troubleshooting

Depth does not open automatically: Press the Digital Crown, open the app list and tap Depth manually. Then check the Watch app on your paired iPhone for water-related settings, including automatic launch if available. Menu wording can vary by software version.
The reading seems inaccurate or does not change: Check that the watch is submerged and fitted securely. Move to a clear, safe area and allow the display a moment to update. Do not use an unexpected reading to decide whether to continue or descend; stop the activity if you cannot rely on your equipment.
The app will not start or appears stuck: Leave the water first. Close and reopen the app, then restart the watch if needed. Check for watchOS updates and make sure the watch has adequate charge. If the problem persists, contact Apple Support.
The display is hard to read: Adjust brightness or wake settings before the activity, and clean and dry the screen. Avoid changing settings while doing anything that requires your attention in the water.
Water remains in the speaker: After leaving the water, use Water Lock’s water-ejection process if prompted, then let the watch dry. Do not push anything into the speaker openings.

Frequently Asked Questions

Does Depth start automatically when I swim?
It may launch automatically when the watch detects submersion, depending on your settings and activity. You can open it manually from the app list if it does not.

Can I use the Depth app for scuba diving?
Do not use it as your scuba dive computer. It lacks essential dive-planning and decompression functions. Use appropriate certified equipment and follow your training.

How deep can Apple Watch Ultra go with Depth?
Apple advises against diving below 40 metres (about 130 feet). Do not use the app beyond that limit, and remember that water resistance is not permanent.

Does Depth save a dive log?
It can provide a basic session summary, including elapsed time and maximum depth. It is not a full dive log or a substitute for records required by your diving practice.

How do I stop Depth after a swim?
Use the on-screen option to end the session if shown, or let the activity finish as you leave the water. Confirm that the app is no longer recording, then rinse and dry the watch when appropriate.

Can I use Depth without an iPhone nearby?
You can open and use the app on the watch itself. Pairing and settings are managed through an iPhone, so configure the watch before heading out.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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