Rowlink

A web app for the Yosuda rowing machine: live dashboard, guided workouts, history and export.
It connects straight to the rower over Web Bluetooth. Nothing to install, no account.

Open Rowlink →

Rowlink replaces the FED Fitness app for Yosuda rowers (YOSUDA-RM-*). Open it in Chrome or Edge on Android, Windows, macOS, ChromeOS or Linux, wake the rower with a stroke, and tap Connect rower.

It also fixes the jumpy numbers other apps show. The rower's own pace and power readings swing 2× from one stroke to the next, so Rowlink works them out from the rower's distance and stroke counters instead.

Features

Live dashboard

• Pace, time, distance, stroke rate, power, knob level and calories, sized to read from the seat
• Rolling 3-minute chart of pace and stroke rate
• Stroke-rate gauge with the target range marked, and a stroke pacer to follow (optional metronome click)
• Tiles turn green when you're on target and amber when you drift off
• Pauses by itself when you stop rowing, and reconnects by itself if Bluetooth drops

Guided workouts, hands-free

• Intervals, benchmarks (500 m, 2000 m, 20 min), steady rows, a pyramid, and 27 classes modelled on the FED app's rower classes
• A countdown and a big "Set knob to 8" prompt before each resistance change. The app assumes you made the change, so you never have to reach for the phone mid-row
• Pace targets scale to your reference pace: set it in Settings, or row a benchmark
• Copy any workout and edit it, or build your own from row and rest segments

Full screen

• One tap fills the screen with the workout and the numbers. On Android it also turns to landscape, even with rotation locked

History and export

• Every row of 20 m or more is saved in the browser, including sessions cut short by a closed tab or dead battery
• Charts of pace, stroke rate, power and knob, with the workout's target bands, plus how much of each step you spent on target
• Export to FIT (Garmin Connect, Strava), TCX, CSV or JSON. Back up and restore all history as one JSON file

Private

• Sessions, workouts and settings stay in your browser. No account, no tracking

Screenshots

Full screen on a phone in landscape, the way it's meant to be used on a rower mount:

Before each resistance change, a prompt counts you down to it:

Phone in portrait: the live dashboard, and the workouts list with each workout's shape and length.

A saved session, with how closely you hit each step's targets:

Screenshots use the built-in simulator, which the connect screen offers when no rower is nearby.

Run it locally

python3 web/serve.py

Then open http://localhost:8080/web/ in Chrome. On Linux, Web Bluetooth may need chrome://flags/#enable-web-bluetooth. No rower nearby? Use Simulator, or Replay a capture of a real session, on the connect screen.

Tests

cd web && npm install && npm test

Project layout

App	web/: plain HTML/JS, no build step (details)
Design notes	PLAN.md: protocol findings, data pipeline, decisions
Recordings	captures/: raw Bluetooth sessions from the real rower, used by the tests and the Replay feature

Not supported

iOS (no Web Bluetooth in any iOS browser), Firefox and Safari.