# Fathomline: Scuba Dive Log — Trip debriefs and lessons

> Trip debriefs and lessons (iPhone/iPad app by Robert Corbin.)

- Source: https://appshunter.io/ios/app/fathomline-scuba-dive-log/id6777667619 (this page in markdown: same URL + `.md`)
- Developer: [Robert Corbin](https://appshunter.io/developer/1890247992)
- Category: Sports, Lifestyle
- Price: $0.99
- Age rating: 4+
- Requires: iOS 17.0 · 5 MB
- Languages: American English
- Released: 2026-06-10
- Data updated: 2026-10-24

## What is Fathomline?

Link existing dives into a named trip, add highlights and next-time notes, and review missing or inconsistent log entries.

HOW IT WORKS
1. Open Trip Debrief from the logbook and select the dives from the trip.
2. Add highlights and next-time notes, then review the record-completeness prompts.
3. Share the debrief. Edits to linked dives appear in the trip; missing dive links are retained and identified.

The private dive logbook and existing reference workflows remain available. Unreadable saved records are preserved rather than reseeded.

WHAT TO KNOW
Completeness prompts are record checks, not dive safety assessments, decompression advice or future dive plans. Sample Diver records are examples. Confirm your own logs with your training, equipment and dive computer.

iPhone and iPad.

## Is Fathomline safe?

Not enough ratings yet to assess Fathomline.

## Is Fathomline legit?

Fathomline: Scuba Dive Log appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for Fathomline is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 5 releases)

### 3.0.1 — 2026-09-30

A clearer App Store name and search details. No other changes in this update.

### 3.0 — 2026-09-14

Trip Debrief

Link existing dives into a named trip, add highlights and next-time notes, and review missing or inconsistent log entries.

1. Open Trip Debrief from the logbook and select the dives from the trip.
2. Add highlights and next-time notes, then review the record-completeness prompts.
3. Share the debrief. Edits to linked dives appear in the trip; missing dive links are retained and identified.

Completeness prompts are record checks, not dive safety assessments, decompression advice or future dive plans. Sample Diver records are examples. Confirm your own logs with your training, equipment and dive computer.

### 2.0.1 — 2026-06-25

This update sharpens the interface: the iPad layout now uses a centered, comfortable reading width instead of stretching edge to edge, so every screen reads as a clean column. iPhone is unchanged; still fully on-device.

### 2.0 — 2026-06-21

Fathomline 2.0 — a pro upgrade from a logbook to a planner + study suite, still 100% offline.

• Minimum-gas / rock-bottom planner: a depth-aware reserve for a buddy pair to surface safely.
• Ascent, safety-stop & flying-after-diving planner: ascent-time profile, the recommended stop, and DAN no-fly intervals for single, repetitive, and multi-day dives.
• Weighting calculator: a real ballast estimate by exposure suit, water type, and cylinder.
• Equipment service tracker with last-serviced and due dates and overdue flags.
• Certification & specialty tracker, and a 25-question dive-theory quiz with explanations and scoring.

Everything is a planning aid and study tool — not a dive computer, and not a substitute for proper training. No account, no network — everything stays on your device.

### 1.2 — 2026-06-15

Version 1.2 - two substantive new features:

CNS OXYGEN TRACKER
Every applicable dive now shows an estimated CNS % on the dive detail screen, calculated from the NOAA single-exposure table (the same table used in every Enriched Air course). See your ppO2 at working depth, the NOAA time limit for that gas, and how close you are to the 80 % single-dive working limit. CNS exposure is shown for nitrox dives and for deep air dives that reach the table range (ppO2 0.6 bar and above). The Tools tab adds a full interactive CNS calculator - enter any gas and depth to get the exposure estimate and the complete NOAA reference table at a glance. The Stats screen shows your total accumulated CNS % across all logged dives where a CNS reading applies.

MILESTONES
A new Milestones card on the Stats screen tracks six categories of personal achievements: total dives (10, 25, 50, 100, 200, 500, 1000), cumulative bottom time (10, 25, 50, 100, 250 hours), depth reached (18, 30, 40 m), distinct sites visited, nitrox dives, and night dives. Each earned milestone shows a gold checkmark; upcoming milestones show a progress bar so you always know how close you are.

All new features are fully offline. CNS tracking is clearly presented as an educational reference - not a real-time dive computer.

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## More apps by Robert Corbin

- [Daily Word Journey](https://appshunter.io/ios/app/daily-word-journey/id6761548266)
- [Hush Secret Text: Encryption](https://appshunter.io/ios/app/hush-secret-text-encryption/id6761658175)
- [Renew Guard](https://appshunter.io/ios/app/renew-guard/id6761755447)
- [Receipt to PDF: Expense Report](https://appshunter.io/ios/app/receipt-to-pdf-expense-report/id6761782025)
- [Route Your Pay: Mileage Log](https://appshunter.io/ios/app/route-your-pay-mileage-log/id6761783719)
- [Tip Arbiter: Tip Calculator](https://appshunter.io/ios/app/tip-arbiter-tip-calculator/id6761786879)

All apps by Robert Corbin: https://appshunter.io/developer/1890247992

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-24.*