# Fathom Dive Planner — Deco planner & logbook > Deco planner & logbook (iPhone/iPad app by Total Immersion.) - Source: https://appshunter.io/ios/app/fathom-dive-planner/id6775766574 (this page in markdown: same URL + `.md`) - Developer: [Total Immersion](https://appshunter.io/developer/408473253) - Category: Sports, Health & Fitness - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 18.0 · 8 MB - Languages: American English - Released: 2026-07-01 - Data updated: 2026-08-10 - User reviews in markdown: https://appshunter.io/ios/app/fathom-dive-planner/id6775766574/reviews.md ## What is Fathom Dive Planner? Fathom is a native iPhone and iPad app for dive planning and logging. Build open- and closed-circuit decompression schedules with configurable gradient factors, then record every dive you make in the built-in logbook, and link each logged dive back to the plan that produced it. Build single- or multi-level dive plans, manage your gas mixes and tanks, and review every parameter that goes into your decompression schedule before you get in the water. After the dive, capture depth, time, gases, tanks, buddies, locations, and tags in a logbook designed for the same workflow. PLANNING • Configurable gradient factors (default GF 20/85) • Multi-level dive plans with automatic gas selection • Full trimix and heliox support, in addition to air and nitrox • Closed-circuit rebreather plans: fixed setpoints with a switch depth, and travel diluent for deep dives • Open-circuit bailout schedules computed from the worst point of the dive • Repetitive dives: tissue loading, CNS, and OTU carry across surface intervals • Custom gas mixes and standard preset catalogue • Tank and cylinder tracking with SAC and per-tank gas usage • Minimum gas (rock-bottom) reserve required to bring you and your buddy back from depth • NDL (no-decompression limit) at any depth • MOD, END, and gas density for every level, with warnings when a mix gets too dense • CNS clock and OTU oxygen exposure tracking LOGBOOK • Log every dive with depth, time, gases, tanks, location, buddies, and tags • Link each logged dive to its original plan • Browse and search your dive history GENERAL • Metric and imperial units throughout • iCloud sync across your iPhone, iPad, and Mac • One purchase unlocks Fathom on iPhone, iPad, and Mac IMPORTANT Fathom is a planning tool, not a substitute for diver training, qualified instruction, or the judgment of a certified dive professional. Always follow the procedures taught in your training agency, the limits of your certification, and your own dive computer. Decompression diving carries inherent risks. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | Fathom Premium - Annual | $6.99 | per year | **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Fathom Premium - Lifetime | $17.99 | one-time | ## Version history (last 5 releases) ### 1.3.0 — 2026-08-06 - Logbook imports on iPhone and iPad. Import Shearwater XML, DL7 and UDDF dive logs directly on iOS, matching what the Mac app already did. - Shearwater Cloud database import. Load a Shearwater Cloud SQLite (.db) database straight into your logbook. - Air-integration tank pressures are now read from Shearwater XML imports. - Better min gas. Rock-bottom now models a two-stage ascent (9 m/min, slowing to 3 m/min at half your maximum depth), with the Help topic updated to match. - Whole-dive SCR is now calculated across all tanks on multi-tank dives. - Dive sites: neighbouring site pins with clustering on every map, typed coordinate entry (DD / DDM / DMS), site duplication. - Weight carried can now be logged per dive. ### 1.2.3 — 2026-07-10 Minor improvements and bugfixes ### 1.2.2 — 2026-07-09 Minor improvements and bugfixes ### 1.2.1 — 2026-07-08 - You can now set a custom MOD for any gas, and the gas card explains each limit. - Minor bugfixes and improvements. ### 1.2.0 — 2026-07-05 Fathom 1.2.0 introduces closed-circuit rebreather planning. CCR PLANNING • Plan fixed-setpoint CCR dives: pick a diluent, set low and high setpoints, and choose the switch depth • Travel diluent for deep dives: descend on a shallower diluent and switch to the bottom diluent at depth • Bailout planning: mark cylinders as usable for bailout and Fathom computes a full open-circuit bailout schedule from the worst point of the dive, including a problem-solving hold at the decision point • Warnings cover both the loop and the bailout: diluent ppO2 against the setpoint, isobaric counterdiffusion on diluent switches, and MOD, END, and gas density across the bailout schedule PLANNING • Multi-level plans can breathe from the same cylinder across levels instead of creating a duplicate gas, and a level can still get its own cylinder when you carry separate tanks of the same mix • Two-tier gas density warnings: an advisory above 5.2 g/L and a strong warning above 6.2 g/L, following Anthony and Mitchell's recommendations • Each repetitive dive now carries its own full dive setup • Gas and tank pickers sort alphabetically, and the catalogue adds Tx12/65 LOGBOOK • The dive detail now leads with the surface interval on repetitive dives FIXES • Opening a saved plan's editor no longer replaces a manually picked gas • Plans using the new CCR features show an update prompt on devices running an older version instead of displaying incorrectly Plus new Help topics covering rebreather planning and gas density. ## Apps similar to Fathom Dive Planner | App | Rating | Price | Category | | --- | --- | --- | --- | | [TheMagic5](https://appshunter.io/ios/app/themagic5/id1343871025) | 4.8 (2,931) | Free | Sports | | [SDI TDI ERDI PFI](https://appshunter.io/ios/app/sdi-tdi-erdi-pfi/id1608231239) | 4.3 (149) | Free | Sports | | [Shearwater Cloud](https://appshunter.io/ios/app/shearwater-cloud/id1185701505) | 2.6 (102) | Free | Sports | | [Padel Point - Track your score](https://appshunter.io/ios/app/padel-point-track-your-score/id6743722817) | 5.0 (2) | Free | Sports | | [Diveplanner Tec & Rec](https://appshunter.io/ios/app/diveplanner-tec-and-rec/id1506985833) | 3.1 (7) | Free | Sports | | [DecoPlanner mobile](https://appshunter.io/ios/app/decoplanner-mobile/id1580563324) | — | Free | Sports | ## More apps by Total Immersion - [Voordeel ~ app voor bol.com](https://appshunter.io/ios/app/voordeel-app-voor-bolcom/id563614410) All apps by Total Immersion: https://appshunter.io/developer/408473253 --- *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 2026-08-10.*