Your phone has all kinds of sensors (accelerometers, gyroscopes, compass) to detect changes in the device’s spatial orientation and change of rate of speed in any direction.
These sensors are quite bad in quality, because they have to be very small, very power efficient and very cheap. Clever software tries to turn those noisy signals into a more or less correct interpretation of the motion of the device. It works remarkably well - considering.
A step tracker is also a piece of software that looks at the mess of signals that sensors (probably mainly the accelerometer) produces and filter out the tell-tale signature of what constitutes ‘a step’. So it counts ‘bounces’ of the phone.
The problem is that it’s not so obvious what kind of phone motion constitutes a step. Can you fake a step by shaking the device? Sometimes you can. Is the signal that counts as a step the same if you wear the device in your coat pocket or if you carry it in the back pocket of your trousers? Probably not.
Depending on the quality of the software that interprets the noisy sensor data, the step counter can be more or less reliable.
(Source: Internet)😅😅
