Can I play on a PC without a sensor?

Yes. Where there is no accelerometer, or permission is denied, it switches to a tap-to-play fallback that chimes the coin sound. Jump detection is available on phones and other devices with a motion sensor.

My iPhone isn't detecting jumps.

iOS requires user permission to use the sensor. Tap "Allow" on the prompt shown when you press start. If it still misses, jump firmly with both feet so the landing impact is clear and detection improves.

Is any data saved or sent?

Only your best hang time is saved, and only in your device's localStorage. The sounds are synthesized on-device, with no external communication or upload.

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2026-07-09

A Jump-and-Move Game Using Your Phone's Motion Sensor (Free)

Sitting all day and moving less? Hold your phone, jump for real, and its accelerometer detects the leap and chimes a coin sound — a motion game that turns light exercise into play. This guide explains how a phone sensor detects a jump, how to play, how to use it to fight a sedentary day or for kids' indoor play, and how to stay safe.

How a phone sensor detects a jump

Smartphones have a built-in accelerometer that measures the acceleration on the device in real time. At rest it reads the pull of gravity (about 9.8), but when you jump and your body goes airborne, it briefly approaches free fall and the value drops.

On landing, there is a large impact spike instead. By measuring that "time in the air," the game counts one jump and can even estimate how high you jumped from the hang time. That is the mechanism behind the jump detection.

When it comes in handy

As a nudge to move your body, it fits many situations.

A short refresher between stretches of remote work or study
Kids' indoor play on rainy days when they can't go outside
A prompt to fight a sedentary day with a bit of light cardio
A mini competition — record jump counts or hang time and compete as a family

How to play (Jump Coin)

The free tool Jump Coin chimes a coin sound when you hold your phone and jump. The sound is synthesized on the fly — no sound files, no external communication.

The steps:

Open Jump Coin on a phone (a device with an accelerometer)
Press start (on iPhone, allow the motion-sensor permission it asks for here)
Grip the phone firmly and jump in place
On a detected jump, a coin chimes and it shows the estimated height from hang time and your best

Playing safely and getting good detection

Safety first. Check that there are no people or objects nearby and that the floor is not slippery, and avoid jumping under low ceilings or near things. Hold the phone firmly with both hands so you don't drop it, and use a strap if you have one.

If detection is unreliable, jump firmly with both feet so the landing impact is clear. On a PC without a sensor, a tap-to-play fallback chimes the coin sound instead.

Try the tool featured in this article — free, right now.

Use Jump Coin

Frequently asked questions

Q. Can I play on a PC without a sensor?: A. Yes. Where there is no accelerometer, or permission is denied, it switches to a tap-to-play fallback that chimes the coin sound. Jump detection is available on phones and other devices with a motion sensor.
Q. My iPhone isn't detecting jumps.: A. iOS requires user permission to use the sensor. Tap "Allow" on the prompt shown when you press start. If it still misses, jump firmly with both feet so the landing impact is clear and detection improves.
Q. Is any data saved or sent?: A. Only your best hang time is saved, and only in your device's localStorage. The sounds are synthesized on-device, with no external communication or upload.