crazyDive is a dive and snorkel logbook. Your Apple Watch records the dive for you — depth, water temperature, GPS position at the surface and, if you want, compass and motion — and your iPhone, iPad or Mac keeps it with its profile, its map and the weather at the time.
| Device | What you need |
|---|---|
| Apple Watch | A model with a depth sensor — any Apple Watch Ultra, or Apple Watch Series 10 or later — running watchOS 26 or later. |
| iPhone | iOS 18 or later, paired with the watch. |
| iPad and Mac | Optional: iPadOS 18 or later, or a Mac with macOS 15 or later. They see your dives through iCloud. |
Recording starts by itself when you go under, and the app turns on Water Lock: the touch screen stops responding so the water can't trigger taps. The screen shows your depth in large type and the dive time, which you can hide in Settings. There is nothing to press: the app detects the descent, the ascent and the surface on its own.
crazyDive detects the surface and starts a countdown. You don't have to do anything:
Below 40% the watch warns you. Below 20%, if automatic battery saving is on, it stops recording motion (the track) to stretch the battery; depth and temperature keep recording.
Snorkel works just like a dive; statistics count it separately.
| Data | Where it comes from |
|---|---|
| Depth | The watch's depth sensor, one reading per second while you are submerged. Below about 6 m, the depth Apple Watch Ultra stores in Health. |
| Water temperature | The watch's sensor: minimum, average and maximum. |
| Position | The watch's GPS at the surface: entry and exit points. |
| Compass and motion | Optional: heading, gyroscope and accelerometer, to estimate the underwater track. |
| Weather | Apple's weather service, for the time and place of the dive: conditions and air temperature. |
| Time of day | Morning, afternoon or night, from the start time. |
Every dive is also saved as a workout in the Health app.
Search by text and use Filters: type (dive or snorkel), date (last month, last 3 months, this year), minimum depth and tags.
"Add dive" logs a dive made without the watch or from before you had the app.
The calendar marks the days you dived. Statistics show dives and snorkels, your deepest dive, total time, the coldest and warmest water, average depth and duration, activity over the last 12 months, your deepest and longest dives and the depth distribution.
"Last dive" and "Total dives" are available in Siri and the Shortcuts app. The small or medium widget shows your last dive.
Each dive's map marks the entry and exit, with a Surface or Sea floor layer. "Show track" draws the estimated track, and "Open in Maps" takes you there. Sites gathers every place you have dived on one map.
Everything is in Settings → Backup.
The app can offer a backup when you save a dive and remind you now and then.
It's automatic. The watch saves the dive and sends it when the iPhone is in range. If one doesn't arrive, open crazyDive on the watch and tap Settings → Apple Watch → Recover dives from Watch on the iPhone. "Clear Watch queue" deletes what the watch still has pending: use it only if those dives are already on the iPhone.
With iCloud turned on, your iPhone, iPad and Mac stay in sync through your account.
| Section | What's there |
|---|---|
| Sensors | Record compass, gyroscope and accelerometer · Ask before each dive |
| Display | Show time during the dive · Automatic battery saving |
| Automatic start and stop | Automatic stop · Stop samples after N min · New dive after N min |
| Backup | Offer backup · Reminder · Create backup · Export · Import · Import backup JSON · Diagnostics |
| Apple Watch | Recover dives from Watch · Clear Watch queue |
No. It records and keeps your dives; it does not calculate decompression or warn you about limits. Always dive with your dive computer.
The watch's sensor, about 6 m. With an Apple Watch Ultra, anything deeper is filled in from the depth the watch stores in Health, down to 40 m.
As a logbook, yes: you can add dives by hand and import them from UDDF. Recording needs a watch with a depth sensor.
Because of Water Lock, which prevents false taps. Turn the Digital Crown to release it.
Open crazyDive on the watch and use Settings → Apple Watch → Recover dives from Watch on the iPhone.
Only in your own iCloud account, if you have it turned on. We have no servers.
From Settings → Diagnostics → Send to support: you can attach the app's log and review it before sending. Or write to support@crazydev.app.
Your dives are stored on your devices and, if you have it turned on, in your own iCloud account. No accounts, no servers of ours, no analytics, no ads. For the weather, the dive's location and time are sent to Apple's weather service; we never receive them.
The details are in the Privacy Policy.