A gym log for people who don't count reps and don't follow a plan.
One HTML file. Add it to your iPhone home screen and it works like an app — offline, no account, data never leaves the phone.
Open the app · How it works · 中文
I tried several workout apps and quit all of them. My training doesn't fit their model: no program, I take whatever machine is free, I scroll my phone between sets and forget to log, and I forget to tap "finish" — once I came back to a 15-hour workout.
So I wrote one around those habits.
Available in English and Chinese. It follows your system language, and you can switch in Settings. Weights are in kg only.
- One tap per set. A new set copies the previous weight and reps and shows what you did last time. Tap ✓ and the rest timer starts.
- Don't feel like counting? Mark a set as "about the same as last time". Estimated sets never count as personal records.
- Forgot to finish? After 10 idle minutes the workout closes itself, ending at your last completed set. You can reopen it the same day.
- No plan? The exercise picker puts what you haven't trained longest at the top. Machine taken? Swap to another exercise for the same muscle in one tap.
- Rest alarm that works on a locked phone, with the silent switch on, while you're in another app. Watching videos between sets? Switch to “Clock timer”, which hands the countdown to the iPhone Clock app via Shortcuts so it rings over anything.
- Warm-up sets, PR detection, per-exercise charts (max weight, estimated 1RM, volume), weekly stats, editable history, JSON backup.
The whole app is a ~1,300-line index.html in vanilla JavaScript: no framework, no build, no backend. A small sw.js handles offline caching.
- A lock-screen alarm without push notifications. Web pages can't run timers in the background. So when you finish a set, the app synthesizes a WAV on the fly — silence as long as your rest period, then a chime — and plays it as media. iOS keeps media playing when locked and ignores the silent switch, so the chime lands on time. The cost: it pauses your music, so there's a mode that doesn't.
- The timer stores an end timestamp, never a running count, so suspension or a page reload can't make it drift.
- Auto-finish without background work. On open, it checks how long you've been idle and backdates the end time to your last set.
- Versioned storage. Data in
localStoragecarries a schema version and migrates step by step; failed writes roll back.
git clone https://github.com/Faust-cloud/gymlog.git && cd gymlog
python3 -m http.server 8000 # open http://localhost:8000