Runs entirely on-device
Every workout is a row in a local SQLite database on your iPhone. No account, no server, no analytics, no telemetry — and it backs up with your normal device backup.
OPEN SOURCE · ON-DEVICE · iOS · v0.1.0
Ischys is a strength-training log that runs entirely on your iPhone — no account, no server, no cloud. Set rows, rest timers, automatic PR detection, an Apple Watch companion and a Lock Screen Live Activity. Not one lift ever leaves the device.
WHAT IT IS
Every workout is a row in a local SQLite database on your iPhone. No account, no server, no analytics, no telemetry — and it backs up with your normal device backup.
An Apple Watch companion to mirror and control a live workout, a Lock Screen Live Activity that ticks your rest timer, and Apple Health — heart rate in, finished workouts out.
Set rows with warmup, drop and failure types. A rest timer. Last session's numbers autofilled. Personal records — best set, estimated 1RM, best volume, max reps — recomputed the moment you finish.
Import a workout CSV export. Take everything back out as CSV or JSON, whenever you like. 736 exercises bundled from the public-domain free-exercise-db.
THE APP
Big number targets, previous-session references, monospace figures that never shift width. Built to be read mid-set with sweaty hands.




PRIVACY
Most trackers ship your training — and everything it implies about your body, schedule and habits — to a cloud you don't control. Ischys has nowhere to send it. All the logic that computes your volume, 1RM estimates, streaks and charts runs in TypeScript on the phone.
There's no account to create and no backend to breach. Your data can't leak from a server that doesn't exist.
It rides along with your normal device backup (iCloud), and you can export a full JSON or CSV copy anytime.
Every line is on GitHub under MIT. "Nothing leaves the device" isn't a policy you have to take on faith — read the code.
INSTALL
Ischys is free on the App Store — one tap to install. It's also open source: if you'd rather build it yourself and see exactly what runs on your phone, you'll need a Mac with Xcode and a free Apple developer account to sign it onto your iPhone.
npm install in frontend/.
npx expo run:ios --device builds a release and installs it. Plug in, unlock, and pick your phone.
# everything runs on the phone — no backend to start $ git clone https://github.com/ischys-app/Ischys.git $ cd Ischys/frontend $ npm install $ npx expo run:ios --device # needs macOS + Xcode ✓ Built Ischys.app ✓ Installed on your iPhone open it — no account, no server, no setup
OPEN SOURCE
Every line is on GitHub under the MIT licence — a React Native / Expo app with a local SQLite database and all the training logic in TypeScript. Read exactly what happens to your data, open an issue, or send a pull request.
ROADMAP
Ischys is v0.1.0. On-device logging, the Apple Watch companion, Live Activity and Apple Health all work today — everything below is where it's going.
SHIPPED
Live on the App Store — free, one tap to install. Building from source is still there for anyone who wants it.
IN PROGRESS
The app is React Native and now builds and runs on Android. The Watch, Live Activity and Health integrations are iOS-only for now; a Google Play release is in the works.
PLANNED
CSV import works today. More formats and a JSON restore are next, so switching trackers never costs you a training history.
PLANNED
Opt-in, on-device sharing of a workout card — nothing uploaded, nothing tracked, just an image you choose to send.
Fully on-device and live on the App Store for iPhone, free. Ischys is strength-only — weight × reps, no cardio. Android now builds and runs, with a Google Play release in the works. If that sounds like the tracker you want to help build, the issues are open.
FAQ
Completely. Ischys is free and open source under the MIT licence — no subscription, no paywall, no ads.
Yes. Ischys runs entirely on your iPhone — no account, no server, no cloud, no analytics. Your training data never leaves your device, so it can't be collected, sold, or breached.
Yes. Everything is on-device, including the 736-exercise catalogue, so Ischys works with no internet connection at all.
Yes — the full source is on GitHub under the MIT licence. You can read exactly what it does with your data.
iPhone (iOS), with an Apple Watch companion, a Lock Screen Live Activity, and Apple Health integration. Android isn't built or tested yet.
Yes. Ischys imports a workout CSV export, and you can export all of your data back out as JSON or CSV whenever you like.
Yes — Ischys is live on the App Store for iPhone, free. It's also open source, so you can build it from source yourself (macOS with Xcode) if you prefer.
Free, MIT-licensed, and running entirely on your phone.