Workout tracker · iOS & Android

The workout tracker that guards your gains.

Kustos is a free, offline-first workout tracker for iOS and Android. Log sets in seconds, keep unlimited routines, and bring your whole history with you: one-tap import from Hevy, Strong, and 6 more apps. Versioned backups and CSV export mean you never lose a rep.

Launching August 2026 on iOS & Android. One email when it's live — nothing else. Privacy

Kustos active workout screen: Push Day with bench press sets logged — 87.5 kg × 9 checked off in lime, last session’s numbers shown beside each set

Why Kustos

Six promises, logged like sets

Built after reading tens of thousands of reviews of other trackers. Every promise here survives the fine print.

Log offline, anywhere

Every set is saved on your device instantly. Basement gym, airplane mode, a ship at sea: logging never needs a connection.

Versioned backups, one-tap restore

Automatic versioned backups for everyone, daily and after workouts. Sign in to add a synced copy, and a new phone gets everything back in one tap.

CSV export, anytime

Your data walks out with you whenever you want. Exporting your own history is never paywalled.

Bring your whole history

One-tap import from 8 apps — Hevy, Strong, JEFIT, FitNotes, Fitbod, Lyfta, StrengthLog, Fleek. Every set, every PR comes along.

A catalog that speaks your gym’s language

450 curated exercises, searchable by muscle and equipment — plus custom exercises when you need them.

Social that’s opt-in, not opt-out

Share finished workouts with training partners if you want. Stay fully private by default if you don’t.

Kustos routines screen with reusable routines organized in folders

Fully free at launch

Unlimited routines. Free.
Your full history. Free, forever.

No credit card. No trial clock. Your own logged history and its export are never paywalled: that’s the promise the name is built on.

Buddy Mode

Lift together, live

Start a session, share a QR code, and see each other’s sets as they happen. Bodyweight-relative scoring keeps a 60 kg and a 100 kg lifter competitive. Real sets from real friends, not streak badges.

Kustos Buddy Mode lobby with a QR code to invite a training partner

Never lose a rep

Backups that just happen

Automatic versioned backups, daily and after workouts. Sign in for a synced copy that restores on a new phone in one tap, or export CSV and keep your own. See exactly what we store.

Kustos Backup & Restore screen with automatic daily backups enabled and a Back Up Now button

Your data, guarded

Nothing to hide, nothing locked in

What we store Guest mode keeps workouts on your device; signing in adds an encrypted-in-transit synced backup.
Export anytime CSV of your workouts and measurements, free for everyone, via the share sheet.
Delete cascades Delete your account and everything tied to it goes too — synced data, social content, the account record itself.

Read the plain-language data page

FAQ

Questions, answered straight

More detail lives in the Help Center.

Does Kustos work offline?

Yes — logging, routines, and history never need a connection. Your sets sync and back up when you’re back online. See exactly what we store.

Do I need an account?

No. Open the app and start logging — no signup and no personal data required to start. An account adds synced backups and optional social later.

Is Kustos free?

Kustos launches fully free: unlimited routines and your full workout history, with CSV export included. No credit card, no trial clock. See what you get.

Can I import from Hevy or Strong?

Yes — one-tap import from 8 apps: Hevy, Strong, JEFIT, FitNotes, Fitbod, Lyfta, StrengthLog, and Fleek. It runs on your device and works in guest mode. See how importing works.

Guard your gains.

Launching August 2026. Be first in line, and bring your history with you.