PocketDeco: Dive Planner

RunDouble C25K

About this app

PocketDeco is a decompression planner for technical divers. It runs the Buhlmann ZHL-16C algorithm with gradient factors entirely on your phone, and it is completely free.

SAFETY

PocketDeco is a planning tool. It is not a substitute for proper training, for certification, or for a dive computer. Do not dive a schedule you are not trained and equipped to dive. Cross-check every plan against a second source such as tables, desktop planning software or your dive computer, and carry a dive computer in the water. Decompression models are approximations and this one is no exception.

THE MODEL

- Buhlmann ZHL-16C, 16 tissue compartments, nitrogen and helium tracked separately
- Gradient factors, GF Low and GF High, set independently
- A separate GF Low and GF High used for CCR bailout plans
- Salt water, fresh water or EN13319 water density
- Ascent rate, descent rate, deco step size and last stop depth all configurable
- Option to force a minimum one minute stop at every step, or to collapse short ascents into the following stop

PROFILES

- Multi-level profiles: add as many dive legs as you need, each with its own depth, time and gas
- Open circuit and closed circuit legs in the same dive, with a set point per CCR leg
- Repetitive dives: add a surface interval and tissue loading is carried forward from the previous dive
- The plan lists the stops: depth, gas and the runtime to leave at, with a row of its own at every gas change
- Turn on Show travel to add the ascents and descents between the stops, and a key explains every marker in the table

GASES

- Air, nitrox and trimix; enter oxygen and helium percentages directly
- Keep a list of deco gases, and the richest usable gas is selected automatically as you ascend, switching at each gas's MOD
- MOD is derived from your maximum ppO2, maximum END and maximum gas density limits
- Choose whether oxygen is counted as narcotic
- MOD can be overridden to a shallower depth on any gas
- You are warned when a gas is not suitable for the depth you asked for

CCR BAILOUT

- A bailout plan is calculated from the end of every closed circuit leg
- The longest of them is highlighted, and any individual bailout plan can be inspected
- Bailout gas volumes use their own RMV, separate from your working RMV

GAS VOLUMES

- Per gas: cylinder size, number of cylinders, fill pressure and reserve
- Required against available volume for every gas in the plan
- An out-of-gas warning when a plan needs more than you are carrying

UNITS

Metres or feet throughout, including depths, ascent and descent rates, stop sizes and MOD.

PRIVACY

PocketDeco requests no Android permissions at all. There is no network access, no account, no sign-in, no analytics, no tracking and no ads. Nothing you type leaves your device, because the app has no means to send it anywhere. Every calculation runs locally.

Free. No in-app purchases, no subscription, no locked features.

What’s new

PocketDeco is free. The paid upgrade has gone, and with it the depth and time limits.

It collects nothing. No permissions, no network code, no account - nothing you type can leave the phone.

The plan is now a table of stops, with a row of its own at every gas change and a key to the markers.

New look, light or dark, meant to be read in sun on a boat.

The ZHL-16C engine is untouched and gives the same schedules as before.