How does your phone track your every step?

Thanks to the various sensors in modern smartphones, smartphones can do more than just communicate. For example, you don't need a dedicated device to count your steps because your phone can do it for you. So how do smartphones count steps?

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How does your smartphone track your steps?

Most smartphones today come equipped with a variety of motion sensors, such as accelerometers, gyroscopes, and GPS. The main sensor that allows your smartphone to track your steps is the built-in accelerometer. This tiny device measures input through an oscillating lever that touches a metal contact point.

This device measures the acceleration of your phone as it moves. This is how your phone knows when to rotate the screen based on how you hold it. The same type of data can be interpreted to track the cadence of your steps as you walk or run. Using accelerometer data, apps analyze your activity using special algorithms to count the number of steps you take each day.

In addition to the accelerometer, some phones also have a gyroscope, which measures rotation and orientation, helping to determine the direction of motion. The gyroscope is not required, but it can supplement the accelerometer data and increase accuracy if present.

These two sources of information are then cross-analyzed to find out how many calories you burned, along with other statistics about your performance. For example, fitness apps use this data to determine how many calories you burned.

Other types of sensors, like altimeters, can also add to this digital portrait of the quality of your workouts. Additionally, some apps compile data from your smartphone and smartwatch to get the most accurate results possible. For example, Google Fit combines step counts from both your phone and your smartwatch.

That’s how your smartphone counts the steps you take. Even if you’re running on a treadmill at home, the accelerometer in your phone is ready to record every move. But it’s not just smartphones; pedometers also use these sensors to track your steps.