I’ve read several reviews and would like to offer my experience with the Alta HR regarding several attributes. Overall, I love this fitness tracker. It is small, sleek, and simple enough to track exactly the features that I want and nothing more for a reasonable price. I am currently on my second Alta HR — I lost the first one and couldn’t get by without it.Device and battery life: I’ve had my current Alta HR for 1 year and 4 months and it is still rocking and rolling. I charge it once/week on Sunday nights and do not have to charge it again throughout the week, even with actively logging several tracked runs and workouts. The great battery life, especially for a continuous heart monitoring device, is one of my favorite features.Design and screen: What drew me to the Alta HR in the first place is the sleek and small design. The screen is just big enough to see the time, heart rate, etc and can easily be worn with any outfit (see also: cheap and colorful replacement bands for ease of matching). It’s a simple feature, but I love that when you turn your wrist upward the screen auto lights up to the home screen. You can customize this home screen— I have mine set to time and heart rate so all I have to do during a workout to see my HR is turn my wrist up. As others have said, the tapping can sometimes be finicky (~20% of the time the first tap attempt doesn’t register), but it’s really not that troublesome. Again, customizing the home screen to the features that are most important to you can resolve most of this frustration.Sleep tracking: I’ve found the sleep tracking to be accurate for the most part. I naturally have a high resting heart rate and it’s likely that Fitbit is underestimating the amount of deep sleep that I get (10% on avg). However, it does a good job of differentiating between sleep and awake and total hours slept. I like that the auto-light up feature of the screen is disabled during sleep. The device and band are very comfortable and I don’t notice them during sleep.Heart rate tracking: I’ve found the heart rate monitor to be VERY accurate. I was not expecting this level of accuracy and have been very impressed. I do not have a strap monitor to compare with, but I have manually monitored my heart rate (neck pulse and a timer) at different intensity levels and found that my Alta HR was always within +\-3 bpm. As others have said, you do need to follow the directions of the device to get accurate heart rates during workout. The device is EXTREMELY accurate when following the directions. If you are going to workout (or do any activity that causes substantial wrist turbulence), you need to move the device 1-2 fingers above the wrist and tighten it an extra loop. This allows the device to maintain a constant and reliable read during motion.The app: The fitbit app is not unique to this device, but I LOVE it. I love that it syncs with both the device and other apps. I can use MyFitnessPal for my food and it auto-imports and uses that information to calculate remaining calories, including ones that you burned through activity and basal caloric burn (if you set a weight goal, the app will show a dial that uses this information and tells you if you are over, under, or on target for the day and by how many calories). It also easily allows me to track water intake. It obviously also has step goals and hourly step goals, as well as active minute goals. All of these goals can be customized, and move reminders for the device can be customized by in the app. The app also uses resting HR and GPS tracked run information to estimate your VO2 max. The device and app also will auto-detect several activities (walking, running, “outdoor sport” like tennis) with 10+ minutes of an elevated heart rate and steps. I really enjoy this feature because I feel it gives me a more accurate read of calorie burn than just entering a “tennis doubles for 20 minutes” activity in MyFitnessPal.Step tracking: Accurate as far as I can tell. Some have complained about not having accurate step counting while pushing a stroller etc— you can still get your steps counted (but not heart rate) by strapping this to your belt loop. I frequently visit manufacturing environments where I cannot have anything in my wrist and strapping the device to my belt loop always yields an expected number of steps.Other features: I like that the devices notifies you about texts and phone calls and scrolls the person and a message preview (can adjust in settings) if you prefer. I did not want my phone on my wrist as a distraction all the time (@apple watch) and the Alta HR level of notifications is perfect. The device is also water resistant: I’ve accidentally taken it in the hot tub for a few minutes multiple times and it’s not been affected except for a temporary cloud over the screen once that went away after a couple days. I’d hesitate to purposely swim with it though.