# MultiDeco > Technical scuba dive decompression calculator with VPM and ZHL-16 models. (iPhone/iPad app by HHS Software Corp..) - Source: https://appshunter.io/ios/app/multideco/id781437836 (this page in markdown: same URL + `.md`) - Developer: [HHS Software Corp.](https://appshunter.io/developer/301978863) - Category: Utilities, Productivity - Price: $48.99 - Rating: 3.90/5 from 11 App Store ratings · 18 written reviews indexed - Age rating: 4+ - Requires: iOS 17.6 · 2 MB - Languages: American English, Czech, Danish, Dutch, Finnish, French (France), German (Germany), Hungarian, Italian, Japanese and 11 more - Released: 2014-03-17 - Data updated: 2026-08-22 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/multideco/id781437836/reviews.md ## What is MultiDeco? A dive decompression calculator for technical scuba divers. MultiDeco presents the VPM and ZHL-16 decompression model and includes VPM-B, VPM-B/E, ZHL model versions and ZHL-16 + GF. The diver can specify any combination of nitrox or trimix, and as many deco gases as required. Planning methods include both OC and Closed Circuit Rebreather. It includes planning for bailouts with SCR and OC legs in a CCR plan. Includes details of ppO2, END, and gas consumptions. This program includes many of the features from the desktop version such as conservatism adjustments, extended stops, adjustable last stops, the planning monitor system and extensive control over many other planning features. Also included is a set of dive planning tools for calculating best mix, maximum operating depth (MOD), END, EAD and other planning considerations. The Mixer utility for blending nitrox and trimix, is included too. ## Key features - VPM and ZHL-16 decompression models - Support for nitrox and trimix - OC and CCR planning - Bailout planning - Gas blending utility - Depth calculation tools ## Chart rankings - #197 in Top Paid · Utilities (US App Store) ## Recent user reviews (10 of 18) All indexed reviews: https://appshunter.io/ios/app/multideco/id781437836/reviews.md ### 1/5 — App Crashing *2025-11-11* Anytime I try to change the model, the app crashes. Is being useless. ### 5/5 — Шикарная прога/Excellent app! *2024-08-14, version 1.104* В программе есть все что нужно. Считает дайвы по VPN и GF. На выбор. Если нужно считать чистый кислород- ставьте Найтрокс 99%. Чистый кислород 100% программа не считает. Do everything I need. Can calculate dive using either VPN and GF models. If You need O2- set nitrox 99. App cant count 100% Oxygen. ### 1/5 — Crashes *2023-11-11* This app does not work on the newest iPhone continuously crashes ### 1/5 — Seriously buggy *2023-06-09* This app is abandoned, use at your own risk. It doesn’t work with the latest iOS update. The back or save buttons crash the app on any device I use. ### 2/5 — Does most of what you want *2022-11-21* 2020 - Buyers be aware that the purchase of this program is not transferable across platforms (mobile or desktop ). If you want to use it on both, you have to buy the program twice. I spoke with Customer Service and they confirmed I would have to purchase twice however that bit of info is not readily found on their website. ### 3/5 — War schon mal besser *2021-05-08, version 1.96* Läuft leider nicht mehr stabil auf dem IPhone 11. Zahlenwerte müssten am Display angepasst werden. Weiße Schrift auf gelben Hintergrund ist leider nicht lesbar. ### 5/5 — Dunkelmodus kann wieder genutzt werden *2021-02-28, version 1.95* Seit dem Update kann der Dunkelmodus wieder genutzt werden. Danke fürs schnelle Nachbessern! ### 4/5 — Do not calculate oxy *2020-10-10, version 1.93* Why purchased program do not calculate 100% o2 ?! ### 4/5 — Good app - but support web page has issues *2018-07-17, version 1.88* I wrote a poor review initially because I misunderstood the interface. Got some support from vendor and now program works well. Still an issue with their web support page however which chokes on any punctuation in comments - and makes it pretty hard to get support ### 2/5 — Leider keine Wartung für kleine Bugs in der App *2018-07-11, version 1.88* Seit über einem Jahr keine neu Version der App. Ich hatte in dieser Zeit einige kleine Fehlerbilder gemeldet. Im Verhältnis dazu die Kosten der App. - 2 Sterne. Ansonsten berechnet die App bisher zuverlässig die Deco für die Tauchgänge. Einziges Manko ist, das die Isobare Gegendiffusion nich berechnet oder angemerkt wird. Das sehe ich bei Gaswechseln im Trimix Bereich ein großes Manko, zumal die Empfehlungen dazu einfach zu berechnen sind. - 1 Stern ## Frequently asked questions about MultiDeco ### What decompression models does MultiDeco use? MultiDeco utilizes the VPM (Variable Permeability Model) and ZHL-16 (Haldane model) decompression models. It specifically includes VPM-B, VPM-B/E, ZHL model versions, and ZHL-16 + GF. ### Can MultiDeco plan for different gas mixes? Yes, divers can specify any combination of nitrox or trimix gases. The app also allows for planning with as many deco gases as required for a dive. ### Does MultiDeco support rebreather planning? Absolutely. MultiDeco supports planning methods for both Open Circuit (OC) and Closed Circuit Rebreather (CCR) systems. It also includes planning for bailouts with SCR and OC legs in a CCR plan. ### What planning tools are included in MultiDeco? The app includes tools for calculating best mix, maximum operating depth (MOD), Equivalent Narcotic Depth (END), Equivalent Air Depth (EAD), and other planning considerations. A Mixer utility for blending nitrox and trimix is also integrated. ### What are the key features from the desktop version available in MultiDeco? MultiDeco incorporates many desktop features, including conservatism adjustments, extended stops, adjustable last stops, the planning monitor system, and extensive control over other planning features. ### What devices is MultiDeco compatible with? MultiDeco is available for iPhone, iPad, and iPod devices. It is designed to run on iOS platforms. ### How often is MultiDeco updated? The latest version of MultiDeco is 1.109, last updated on November 11, 2025. Updates typically occur to improve functionality and compatibility. ### What is the price of MultiDeco? MultiDeco is a paid application, priced at $48.99. This one-time purchase grants access to all its decompression planning features. ## Version history (last 5 releases) ### 1.111 — 2026-07-30 Bug fix for bail out tank selection issue. ### 1.110 — 2026-05-04 Updated for iOS 26 changes. ### 1.109 — 2025-11-11 Further updates for iOS26. ### 1.108 — 2025-11-07 Updated again for iOS26. ### 1.107 — 2025-10-27 Update for iOS26. ## Apps similar to MultiDeco | App | Rating | Price | Category | | --- | --- | --- | --- | | [Arcus Trimix Blender](https://appshunter.io/ios/app/arcus-trimix-blender/id6480379323) | — | Free | Utilities | | [Diver Tools](https://appshunter.io/ios/app/diver-tools/id1613178459) | — | $9.99 | Utilities | | [Buoyancy Calc](https://appshunter.io/ios/app/buoyancy-calc/id1482332472) | 3.1 (25) | Free | Utilities | | [MyFathom](https://appshunter.io/ios/app/myfathom/id6466220916) | — | Free | Utilities | | [Deep Tools](https://appshunter.io/ios/app/deep-tools/id1476093876) | 4.6 (93) | Free | Utilities | | [Cylindex -Cylinder Inspections](https://appshunter.io/ios/app/cylindex-cylinder-inspections/id6741502559) | — | Free | Utilities | ## More apps by HHS Software Corp. - [V-Planner](https://appshunter.io/ios/app/v-planner/id301978860) All apps by HHS Software Corp.: https://appshunter.io/developer/301978863 --- *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 2026-08-22.*