Wellness · checked 2026-10-20Can I vibecode Strong PRO?
YES· one-shottable
A lifting log is a small data model: exercises, sets of weight and reps, templates, rest timers and a few charts. An agent can build that as an installable web app on IndexedDB in one sitting, with an importer for the CSV that Strong exports. What you give up is the polish of a native app used one-handed between sets, the Apple Watch companion, Health or Health Connect sync, and the fact that data kept in a browser needs your own backups. Free apps like Liftosaur and wger also cover the same ground without any building.
$4.99/moprice
$60you'd save a year
one sittingbuild time
—people replaced it
What you need on hand.
DifficultyBeginner · No setup beyond your agent.
TimeOne to two hours, plus getting it onto your phone
- Claude Code, Codex or CursorAny of them can run the prompt.
- Node.js 22Only needed to build; the result is a folder of static files.
- HTTPS hosting for the built folderA free static host or a tunnel such as Tailscale or Cloudflare Tunnel; phones install PWAs only from HTTPS.
- Your Strong CSV exportSettings > Export Strong Data on iPhone, Settings > Export Data on Android.
Before you buildStrong's free version logs unlimited workouts with 3 custom routines. If three routines are enough for you, you may not need to pay or build anything.
- 1. Install one agent: Claude Code, Codex, Cursor.
- 2. Make an empty folder and open it in the agent.
- 3. Paste the prompt below, press enter, and answer its questions as it builds.
The prompt
Build me a gym workout logger to replace Strong. Requirements: - TypeScript + Vite + React, built as an installable PWA (`vite-plugin-pwa`) that works offline. `npm run dev` serves http://localhost:4900; `npm run build` makes a static folder I can host anywhere. - Storage: IndexedDB through `dexie` in the browser: exercises (name, muscle group, equipment, custom flag), templates, workouts, sets (weight, reps, RPE, type: warm-up, normal, drop, failure), bodyweight. - Logging screen made for one thumb: pick a template or start empty, add exercises, enter weight and reps per set, tick to finish it. Show last session's numbers beside each set. Keep the screen awake with the Wake Lock API during a workout. - Rest timer that starts on each ticked set, vibrates and sends a notification where the browser allows it. Supersets by grouping exercises. Unlimited templates; edit or delete any past workout. - Exercise page: best sets, estimated 1RM with the Epley formula, a volume chart and personal-record flags (`uplot`), plus a plate calculator with a bar weight and plate inventory in kg or lb. - Import: `Import Strong CSV` reads the file Strong exports (match columns by header name, print the headers it could not map) and skips workouts that already exist. - Backup: export everything to one JSON file and restore from it; remind me weekly, because browser storage can be cleared. - Single user. No accounts, no telemetry, local-first. - Out of scope: Apple Watch, Apple Health and Health Connect sync, social features, program generators. - README: hosting over HTTPS (a phone cannot install a plain http address), adding it to the home screen and the backup routine.
Opens your agent with the prompt filled in, you press enter. Or copy it and paste it into an empty folder.
Then keep going
Next prompts, same folder.
The first prompt builds the core. Run these one at a time in the same folder to grow it into your own Strong PRO.
Add optional sync to the workout logger in this folder. Requirements: - A small Node.js 22 server (Fastify + better-sqlite3) in ./server that stores the app's JSON export per user, guarded by one shared token from .env; no user accounts. - The PWA pushes changes after each finished workout and pulls on start. Every record carries an updatedAt and a UUID; the newest edit wins and deletes are kept as tombstones. - Works offline: queue changes and retry; show 'last synced' on the settings page. - Update the README with how to run the server behind HTTPS.
Add simple progression suggestions to the workout logger in this folder. Requirements: - Per exercise, choose a rule: add a fixed increment after all sets hit the target reps; double progression inside a rep range; or keep weight and add a rep. - Show the suggested weight and reps as a faded placeholder in each set row, editable. - Respect the plate inventory: round to the nearest loadable weight. - Write unit tests for the three rules. - Update the README.
Add body measurements to the workout logger in this folder. Requirements: - A measurements page with entries for bodyweight, body fat percentage and tape measurements per body part, each with a date and a note, stored in IndexedDB. - A line chart per measurement with a 7-day moving average. - Optional progress photos stored as blobs in IndexedDB, shown in a date-ordered grid, never uploaded. - Include them in the JSON backup. - Update the README.
What you lose
- The Apple Watch app for logging sets from the wrist
- Sync with Apple Health, Google Health Connect and MyFitnessPal
- A native app's feel and reliability on a gym-floor phone
- Strong Cloud: the same history on every device without setting up anything
- Siri Shortcuts and share links for workouts and templates
Why people still pay
Most people pay for the speed: opening the app and logging a set takes one thumb, last session's numbers are right there and it just works on every phone and watch. The price is a few dollars, and the history is the thing they'd hate to lose.
Strong PRO or your own copy?
Over
Your usage
3h ×$/h
Strong PRO, 1 yr$60
Your own copy, 1 yr$4running + build session
You keep$56pays for itself in the first month
Estimate · Static hosting and a tunnel are free at this size, and there is no server to run. The build is token usage on your agent plan.
Take your data, then cancel.
1 · Take your data out of Strong PRO
- 1iPhone: open Settings in the app and choose Export Strong Data. Android: Settings, then Export Data.
- 2You get a spreadsheet-friendly CSV of your workouts. Strong says exported files can't be imported back into Strong.
- 3Individual workouts and templates can also be shared through share links; more export options were promised in future updates.
- 4Templates and charts are not part of what we found in the export help, so note the routines you rely on.
2 · Cancel Strong PRO
- 1iPhone: Settings, your name, then iTunes & App Store, tap your Apple ID, View Apple ID, Subscriptions, choose Strong PRO and cancel there.
- 2Android: open Google Play, tap Menu, then Subscriptions, tap Strong and choose Cancel Subscription.
- 3You keep PRO until the expiry date. If you no longer see a Cancel button, the subscription is already cancelled.
- 4Deleting your Strong account does not cancel the subscription: cancel in the store first.
- Strong says your workout data remains available on the free version and you are never locked out.
- Refunds go through Apple (reportaproblem.apple.com) or Google; Google allows a direct request within 48 hours of purchase.
- Deleting your account removes your workout history for good, so export the CSV before you do.
- Free accounts keep 3 custom routines, so decide which templates you want before the downgrade.
Checked 2026-10-20 against Strong PRO's docs: 1, 2, 3, 4, 5, 6
The escape hatch
Don't feel like building it? These are already free.
wgerOpen sourceAGPL-3.0 self-hosted workout, nutrition and weight tracker with an exercise library and a REST API.★ 7.2k · active Oct 2026 · docker to self-host
Web, Android, iOSVisit ↗LiftosaurOpen sourceAGPL-3.0 weightlifting tracker that runs as a PWA and as thin iOS and Android apps, with programmable progression.★ 749 · active Oct 2026 · they host it
Web, Android, iOSVisit ↗FlexifyOpen sourceMIT-licensed offline-first workout tracker with plans, graphs and a rest timer; on F-Droid and Google Play.★ 449 · active Oct 2026 · one-click install
AndroidVisit ↗
Web, Android, iOSVisit ↗LiftosaurOpen sourceAGPL-3.0 weightlifting tracker that runs as a PWA and as thin iOS and Android apps, with programmable progression.★ 749 · active Oct 2026 · they host it
Web, Android, iOSVisit ↗FlexifyOpen sourceMIT-licensed offline-first workout tracker with plans, graphs and a rest timer; on F-Droid and Google Play.★ 449 · active Oct 2026 · one-click install
AndroidVisit ↗
The numbers
Strong PRO pricing
| Plan | Monthly | Annual, per month | What you get |
|---|---|---|---|
| Free | $0 | $0 | Unlimited workouts, 3 custom routines. Strong says your workout data stays available without PRO and the free version never locks you out. |
| Strong PRO | $4.99 | $2.50 | Unlimited workout templates, body-part measurements, all charts, plate calculator, warm-up calculator, custom icons and themes. |
| Strong PRO Forever | custom | — | Same PRO features, one payment. |
- Free tier
- 3 custom routines; no body-part measurements, plate or warm-up calculator, or the full set of charts.
- Billing
- Bought as an in-app purchase on the App Store or Google Play, so billing, renewal and refunds go through Apple or Google. Strong has no web checkout on its site.
- Hidden costs
- The price depends on your store and region. Apple Watch and Apple Health work with the iPhone app; nothing else is sold on top.
- Source
- apps.apple.com
Also on the list
Related apps
Free logs unlimited workouts but keeps you to 3 custom routines, per the App Store description.
Yes. An AI coding agent such as Claude Code, Codex or Cursor can build a usable personal version in one session with the prompt on this page, running on your own machine.
About $4.99 a month on the Strong PRO (1 month) plan, $59.88 a year (checked 2026-10-20).
The Apple Watch app for logging sets from the wrist; Sync with Apple Health, Google Health Connect and MyFitnessPal; A native app's feel and reliability on a gym-floor phone; Strong Cloud: the same history on every device without setting up anything; Siri Shortcuts and share links for workouts and templates. If any of those matter to you, keep paying.
Yes: wger (open source), Liftosaur (open source), Flexify (open source).