Sealed by default
Your log is locked on your phone before it's saved anywhere, with keys that never leave it. If someone broke into our servers tomorrow, they'd carry away noise.
Training is personal.
Kass keeps it that way.
Kass is a training app for coaches and their clients. Every session, every weight, every note about your body is sealed between the two of you before it leaves your phone. The server that runs Kass can't read any of it — and neither can we.
next: GSLP 2.1
Start
| Squat | 82.5 kg | 3×5 |
|---|---|---|
| Overhead press | 47.5 kg | 3×5 |
| Chin-up | bodyweight | max reps |
Weights worked out from your last session. Everything editable.
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Nobody's business but yours
A training log is a record of a body: what it can lift, where it's injured, what it weighs, when it's alone in a building. Kass treats it that way.
The next session is always ready
Kass works out your next weights from what you actually lifted — including the session where everything went wrong. Walk in, tap Start, train.
Built for basement gyms
Signal comes and goes; your log doesn't. Kass keeps working offline, and a set, once tapped, is never lost.
Your history is yours for life
Change coaches and your log stays whole, because it belongs to the person who trained it. A new coach joins your story — they don't restart it.
For coaches
Write a programme once and give each client their own living copy — it adapts to how they actually train, without touching anyone else's. And no client can ever see another client's log: not because of a permission setting, but because each person's Kass is genuinely theirs, sealed to them alone.
Your programmes, your client list, and your notes stay in your own Kass, just as sealed as theirs.
How private is private?
- Encrypted before it leaves your phone
- Weights, reps, bodyweight, injuries, messages — all of it is sealed on your device. The server stores and delivers sealed records it cannot open.
- No big database of everyone
- Each person's Kass stands alone. There is no shared pool of training data to mine, sell, or leak — nothing readable exists to take.
- AI only if you ask
- Kass works completely without it. Switch it on and it's a disclosed guest — everything it writes is marked 🤖, and your name never leaves the building.
Kass is in private training
Right now, Kass is being built around one coach and one client, session by session, in a real gym. If you're one of its people, sign in below. If you'd like Kass for your clients — it isn't open yet, but it's getting there.
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