Tremor Check: Is It Shaking?

Is that surface really vibrating? Measure it. Tremor Check turns your iPhone's built-in motion sensors into a precision vibration meter for whatever surface the phone is resting on — a desk, a table, a nightstand, a shelf, a washing machine. The sensors detect movement far smaller than you can feel, and the app tells you plainly what's happening. Clear answers, live A steady green "This surface is still" when nothing is moving. A yellow "Brief vibration" for short bumps — with a checklist of everyday causes like a passing truck, a door closing, or an appliance in its spin cycle. And a red "Vibration detected" with measured intensity and duration when the surface is continuously moving. Alerts on your wrist Set your sensitivity, and if sustained vibration is detected the companion Apple Watch app taps your wrist. Alerts stay on screen until you dismiss them — on the phone and the watch, in sync. A log for the hours you weren't looking Leave it monitoring overnight or while you're away from the room. The vibration log records every detection with time, intensity, and duration for the last 24 hours — or shows you that nothing happened at all. Live vibration trace with your alert threshold One-tap calibration to any surface Adjustable sensitivity (5–50 mg) Brief bumps explained with common causes Apple Watch alerts with measured peak 24-hour detection log, clearable anytime Free. No ads. No accounts. No tracking. Works completely offline. Private by design — every measurement stays on your device. The app never connects to the internet. Note: Tremor Check measures only the movement of the surface your iPhone is resting on. It is not an earthquake detection or early-warning service.