A Rowing Research Tool for iOS
Measure
Wobble
You can't improve what you don't measure. Wobble gives rowing teams a real-time stability score so you have something concrete to work toward. Free to download. No subscriptions.
How It Works
One Number.
Real Insight.
Attach your iPhone to the craft in any orientation. Wobble automatically detects how it's mounted and orients itself accordingly. From there, it continuously computes the Wobble Factor: a single stability score derived from the phone's motion sensors. Lower is more stable. Stroke rate and speed are displayed alongside it, giving the team the full picture in real time.
The Wobble Factor
A single derived stability score. Lower means the craft is more stable. Watch it in real time as the team adjusts.
Any Mounting Orientation
Attach the phone however is convenient. Wobble auto-detects orientation and compensates. No manual calibration needed.
Live Display
Wobble Factor, stroke rate, and speed — all on screen in real time as the team rows.
No Extra Hardware
Just an iPhone attached to the craft. No sensors to buy, no devices to pair, no subscriptions. Free to download.
Built for the Cox Seat
Mount the phone where the coxswain can see it. The Wobble Factor becomes part of their real-time feedback. They can see the number respond as the crew adjusts, and call what actually moves it.
The Observation
Where It Started
I'm Alex North. I've been involved with crew for the last three years, mostly as a rower, but also as a coxswain. During crew practice on Saturday, March 14, 2026, I noticed that rowing at 36 strokes per minute felt more stable with less effort than rowing at 32 SR, even with greater power output. That observation, and the question of why, is the foundation of this research.
Available on iOS
A Research Tool,
Not a Black Box
Wobble doesn't tell you what to do. It gives you a number, and lets your team figure out how to improve it. That's the point.
