WHAT IS ACTIVITY TRACKER? 
An activity tracker is a device or application for monitoring and tracking fitness-related metrics such as distance walked or run, calorie consumption, and in some cases heartbeat and quality of sleep. The term is now primarily used for dedicated electronic monitoring devices that are synced, in many cases wirelessly, to a computer or smartphone for long-term data tracking, an example of wearable technology. There are also independent smartphone and Facebook apps.
HOW IT WORKS?
Activity tracker comes is a shape of a band. Or looks like a smart watch. These bands are call fitness band. These bands are work with your smartphone. You just have to download your mobile supported application from your respective store (Android/iOS/Windows/Blackberry). Before you buy any fitness band make sure that your smartphone works with the band. Some of the bands works with Android, iOS and Windows and some of not. Most of the band does not work with Blackberry. So blackberry user do a little bit research before you buy any fitness band.
WHY FITNESS BAND? 
We live in very busy world. Everyone is busy at their work. Most of us do not have time to take care of our health. Here we need a band which will act as your all time virtual doctor. This band will monitor all you activities all the day. Your heard beat, blood pressure, walking steps etc. Even when you sleep it will measure your sleep pattern.
HOW EASY TO USE THIS ?
These fitness bands are very easy to use. You just need a smart phone. I will say if you can operate your smartphone then you will be fine with this revolutionary gadget.
WHERE CAN I DOWNLOAD APPLICATION?
Fitness band application are varies to company to company. Suppose if you have a Sony fitness band and you have a MI fitness app. This will not work. If need to download Sony fitness app only. There are few app in the market which allow you to connect all companies band. 
Android user download apps from Play Store, iOS form iTune and rest are form their respective stores.
WHERE CAN I BUY IT?
A lot of fitness band are available in the online market. Like amazon, flipkart etc. Before you buy make sure that your phone support the band. This bands price starting form Rs. 999/- in Indian market. You can also have a look on the online shopping site for updated price. To get update price in India click here.
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