Demystifying Mysterious Things

Activity Trackers

An activity tracker has a number of tiny sensors inside it that can track how the user wearing it moves. For example, an activity tracker might track the number of steps you take, stairs you climb, calories you burn, miles you walk, and can even track your sleep patterns. The main sensor for most activity trackers is called an accelerometer.

Mobile Phones

Did you know that most modern day mobile phones also have an accelerometer? It's the sensor that determines if you're viewing your phone in portrait or landscape view (the orientation) and can change the display accordingly.


A Pedometer is the name for a basic accelerometer that usually only measures steps taken and overall distance travelled.


Many cameras have accelerometers to help stablize images. They help to make sure photos are taken when the camera isn't moving as much to avoid blurry photos.

Fun facts

Facts about activity trackers.


First heart-rate monitors launched


Number of adults using wearable devices in 2015


Year Fitbit first available


Wearables revenue by 2020

"Walking 10,000 steps a day reduce cancer rates by 30-70%"

National Institutes of Health

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