I've been on the verge of getting an "activity tracker" for a couple years but couldn't really find one that had the features I wanted w/o also having GPS and other more technical stuff. All I really wanted was to be able to tell the time and get my heart rate during spin class and my weekend walks - that's it. Now I have the Charge HR and I have a few extra bells and whistles but it's not too techy to overwhelm or confuse me. (And I don't have to use or pay attention to the other bells & whistles if I don't want to.) I got my Charge HR about a month ago for my birthday and the App on my iPhone 5C is super easy to use and relatively intuitive. (Again, if I can figure it out, it doesn't require a ton of time or attention.) I've only had one hiccup so far and that was that it didn't want to charge the other night. I played around with the charging cable and kept syncing it with my phone and it eventually started charging. Other than that, I really love this.

I purchased the Fitbit HR as a more sleek alternative to my Polar Watch and chest band to be used primarily while running. I am very disappointed with the accuracy of the HR feature. On casual runs, it is showing my heart rate as being at or near maximum when I know it's at least 20-30 BPM slower. I have run comparison tests with my Polar watch as well as treadmill heart rate monitors and the old fashion way of counting beats to confirm the inaccuracies. Yes, I have followed the instructions on how to wear the Fitbit while excercising.

The product does appear to provide reasonably accurate distance and heart rate information while walking. If that's your primary use for the Fitbit, I think you will like it.

I have owned and reviewed every model of Fitbit since they debuted, and over 100 other fitness trackers. I bought the Fitbit Charge HR. The heart rate feature works well for me, it matched a chest band heart rate monitor well. I like the heart rate zone indicator icon, which inspires me to do more vigorous workouts. For best accuracy, I put it farther up my wrist when I want to track a workout with heart rate. While I loved the Garmin bands, you have to wear a separate heart rate monitor with them to track heart rate, and that's a step I don't like to take.

Another feature that made me pop to buy it is the smart notifications for incoming calls. I don't wear my phone all day, and this way I'm alerted that there is a call even if my phone is elsewhere in my house.

The Charge HR has a buckle band which I far prefer so I don't fear it popping off, although I had no problem with the Charge band, I had lots of struggle with the Flex band.

The workout tracking function is great, press the button to start and stop tracking for specific workouts, then view details on the app or web site. It doesn't have GPS for speed and distance, although you can use the app to track your workout with GPS if you wish, and view the map afterward.

I love the automatic sleep detection and recording, with older models I always forgot to start or stop a sleep tracking session.

The Friends feature also inspires me to stay at the top of the Leaderboard vs. my friends.

I have Fitbit history going back several years and it is interesting to compare my stats now with past years. The diet tracking feature, weights, etc. are useful.

I received review models of the Charge, Charge HR and Surge, which I was required to return to the company after the review. I bought the Charge HR and I am very happy with it.