Zenhold
O₂ and CO₂ apnea tables that never lose your session — built for freedivers, spearfishers and anyone training a calmer breath.
Coming soon to the App StoreWhy Zenhold
- Tables from your own max hold. Take the guided max-hold test once; Zenhold generates your O₂ and CO₂ tables from it — with conservative freediving limits (CO₂ holds never exceed 50 % of your max).
- A timer that cannot lose your session. Timing is wall-clock based, so it stays exact when you lock the screen or switch apps. The current phase and countdown live on your Lock Screen and in the Dynamic Island.
- Pause whenever you need to. One stray tap never kills a 20-minute session.
- Cues you can follow with your eyes closed. Voice and vibration for every phase — and the voice ducks your podcast instead of stopping it.
- Apple Watch app (Lifetime Pro). Run a table from your wrist with the phone in your pocket: one buzz to breathe, two to hold, a light tap three seconds before a hold. The watch keeps its own clock, so it carries on with your wrist down — and the session lands in your history and Apple Health afterwards.
- Any other watch, too. Phase alerts mirror to Garmin and the rest as silent notifications, with the same one/two-buzz language.
- Apple Health. Finished sessions are written to Health as mindful minutes — write-only, straight into your own Health store.
More than tables
Breathwork
Box breathing, 4-7-8, coherent breathing and extended exhale — paced sessions with the same calm guidance.
Measure
BOLT test with interpretation bands, a free-hold stopwatch, and the guided max-hold re-test.
Training plan
Pick your training days, get a reminder, keep a streak. Zenhold alternates CO₂ and O₂ days and warns when you train too often — two to three sessions a week is what coaches recommend.
Breathing buddies
Follow a plain circle, or a little companion whose belly rises and falls with you — it strains and relaxes through the hold along with you.
Free, and Lifetime Pro
The core loop is free forever: the max-hold test, a daily O₂ and a daily CO₂ table, the full session engine, cues, breathwork, recent history and Health sync.
Lifetime Pro (€5.99, one-time) adds the Apple Watch app, fully custom tables, unlimited history with statistics and personal-best charts, auto-progressing tables that adapt to how each session felt, CSV export, and all breathing buddies. No subscription, no account, no tracking — ever.
Languages
Deutsch · English · Español · Français — Zenhold follows your system language and lets you override it in Settings.
Train safely
Zenhold is for dry breath-hold training. Never train in or near water, and never while standing, driving or operating machinery. Stop at any dizziness. Breath-hold training is not medical advice — talk to a doctor first if you have cardiovascular or respiratory conditions, or are pregnant.