The Wobble Factor is a real-time stability score calculated from your iPhone's motion sensors. It's a single number that reflects how much the craft is moving in unwanted ways during a row. Lower means more stable. The goal is to give your team something concrete to observe and work toward improving.
Any iPhone with Core Motion support — which covers every iPhone from the 5s onward. The app requires iOS 16 or later. No additional accessories are required beyond a way to attach the phone to the craft.
No. Wobble automatically detects how the phone is oriented when attached to the craft and compensates accordingly. Mount it however is convenient and secure — no manual configuration needed.
Yes. The Wobble Factor is computed from the motion of the craft regardless of boat type. It's relevant to any shell — single, double, quad, eight, sweep, or scull.
Yes. Your session data is stored on your device and, if iCloud is enabled, in your private iCloud account — which only you can access. We do not collect, transmit, or have access to your data. See our Privacy Policy for full details.
First, confirm that Motion & Fitness permission is enabled for Wobble in Settings → Privacy & Security → Motion & Fitness. Make sure the phone is securely attached to the craft and not moving freely in a bag or pocket. If issues persist, close and reopen the app and start a new session.
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