ATMOS vs U
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
ATMOS
Easily sync and manage your dive logs wirelessly from compatible dive computers. View device information, edit log details, and export your data in UDDF format. Integrates with HealthKit to share dive-related health metrics.
- Wireless dive log syncing
- Dive computer information
- Edit dive log details
- Export logs to UDDF
- HealthKit integration
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ATMOS App is the best companion of Mission One and Mission2, Mission3 dive computer. You can use ATMOS App to : ● Wirelessly sync your device's divelogs. ● Check device information. ● Edit divelog information. ● Export divelog to UDDF format. ATMOS use HealthKit to export your Mission2 health data (Steps, Calories, Sleep, Heart rate) into the Health app. Official website : https://www.atmos.app FaceBook fan page: https://www.facebook.com/atmosocean/ Follow us on Instagram : @atmos_ocean
U
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U-Dive is an Apple Watch companion for freediving and snorkel training. Put on your watch, get in the water — it handles the rest. ◆ On Apple Watch • Automatic submersion & dive detection — recording starts hands-free • Live depth and water temperature (depth display capped at 6 m in this release) • Continuous heart-rate recording during dives — watch your mammalian dive reflex • Surface-interval timer with haptic surfacing alert • Custom depth alerts with haptic feedback • Personal max-depth record notifications • GPS entry/exit coordinates for every dive • Action Button support: start a session, flag a dive, review history • Auto Water Lock — long-press the crown to end & save • Built-in dive simulator to try the full flow on dry land ◆ On iPhone • Dive-spot map with favorites, notes and custom icons • Import Google My Maps layers (KML) • Paste a Google Maps share link to create a spot • Full dive log: depth profile, heart rate, duration and coordinates • Share and export your dives ◆ About Lite This release uses Apple's shallow-depth API: depth display is capped at 6 m, while time, heart rate and GPS keep recording beyond it. A full-depth version is in progress. ◆ Requirements • Depth and auto dive detection require an Apple Watch Ultra (depth gauge) • Other Apple Watch models work in manual mode (HR, GPS, timers, log) • The iPhone app manages spots and logs; the watch app runs independently ◆ Safety This app is not a dive computer and must not be used for dive safety or decompression decisions. Not for scuba diving. Freediving is dangerous — never dive alone, follow one-up-one-down, and get certified training.
Screenshots
Verdict
The clearest difference is update cadence: U at every 2 weeks against ATMOS's every 6 weeks. ATMOS's advantage is iOS requirement (15.0 vs 26.4). On price, ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
ATMOS ships an update every 6 weeks, U every 2 weeks. The most recent releases landed on November 2, 2026 and October 29, 2026 respectively.
| Parameter | ATMOS | U |
|---|---|---|
| Price | Free | Free |
| Rating | 1.7 (23 ratings) — better | — |
| Positive reviews | 7.7% of reviews | — |
| Number of ratings | 23 — better | — |
| Update frequency | Every 6 weeks | Every 2 weeks — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPod | iPhone, Apple Watch |
| Requires iOS | 15.0 — better | 26.4 |
| Further details — not scored | ||
| Size | 119 MB | 10 MB |
| Age rating | 4+ | 4+ |
| Developer | ATMOS CO., LTD. | Yao YungTai |
In-app purchases
ATMOS
No in-app purchases
U
No in-app purchases









