Fitness trackers did well in 2015 but some such as the popular FitBit faced legal issues over the accuracy of the health data they dispensed.
Here is a report that goes into some of the hurdles the trackers have run into – http://www.dailymail.co.uk/health/article-3390533/Are-expensive-fitness-trackers-sports-watches-worth-money-Investigation-reveals-ones-accurate.html
I started using a basic health band recently – it came as a Christmas gift for me. The steps you walk and calories burnt appear in an app, not on the band. No complaints as I am not concerned about its accuracy levels.
Just monitoring the data is fun and it encourages me to walk more! Most 2016 tech projections see fitness trackers losing ground. I like the wearable thrill, though!
G Joslin Vethakumar