Sym Junk

SymJunk is a fast, offline-first companion for configuring your CCR dive

computer and rebreather head over Bluetooth — so you set everything up calmly on

the surface instead of squinting at tiny buttons on the unit.

CONFIGURE EVERYTHING, OFFLINE

• Edit screens, gases, gradient factors, setpoints, deco and more — all on your

phone, no connection needed.

• Save presets per category and pick them with one tap.

• Three colour themes; metric or imperial.

ONE-TAP FLEET SYNC

• Mark your handset, HUD and CCR head, then push your settings to all of them in

a single sync — with a clear before/after overview of exactly what changed.

• The clock and time zone are set correctly on every device.

DIVE LOGS & MAP

• Download your dives and view depth, temperature, pO₂ and tank-pressure

profiles.

• See your dives on a map. Add your own dive-site name and location to any dive

— with type-ahead so your favourite sites autofill.

• Dive-site totals, ranked by number of dives.

OFFLINE MAPS

• Download a dive area for offline use, so the map works with no signal.

REBREATHER TOOLS

• Live CCR-head monitor: cells, setpoint, tank pressures, battery health and

more.

• Vacuum/positive test with an adjustable timer and live loop Δp.

• Calibration guide that follows the head live.

• Step-by-step assembly and calibration checklists.

WAYPOINT PLANNING

• Plan waypoints on a map and upload them to your computer.

PRIVACY BY DESIGN

• No account, no ads, no tracking. Your data stays on your phone. The only

internet use is map tiles and place-name search.

SymJunk is an independent hobby app and is NOT affiliated with, or endorsed by,

Halcyon or Oxygen Scientific. All brand and product names belong to their

respective owners. This is experimental software and not a dive-safety device —

always verify every setting on the dive computer itself and rely on your training

and certified equipment.

Free to use, with an optional one-time Pro upgrade for fleet sync, waypoint

upload and the live head monitor.