Update 1/1/2020: My wife and I have both been using this watch on nearly a daily basis. Our conclusion is that this watch is just not accurate enough to provide us meaningful information. We're not looking for precision, but something that is close to 'a good general idea' would be nice. The heart rate monitor will fluctuate wildly (easily 30+ bpm) in just the few seconds the watch is illuminated to see your rate. Other issues are as noted in my original review. So, although asked a couple times to adjust my rating to 5-star, aside from the ethical issue (and can only assume others provided 5-star for the "buy one, get one" offer), I just can't recommend this watch.The Blackview BV-SW4019 (from back of watch, BV-SW001 from box, BV-SW01 from ad, and appears to be available under several different manufacturer names) Smartwatch has a nice size face, bright and easy to read indoors and out. Wrist band is smooth and comfortable, but too long in my opinion. Could easily lose about a third of the total length. Love the quick connect USB, but it does mean carrying an extra cable if taking this watch on travels. Price, in this hot, overpriced market is relatively inexpensive. This is my first foray into this market.As far as function, this watch covers the basics, in a basic way. I’ve been using this watch for 10 days (a VERY short trial period), on a daily basis for general use and workouts, and sleep monitoring. I have not used the notification, alarm or music functions. Battery life is great, currently at 55%. The booklet provided offers the basics for the watch, the rest is up to you to fiddle around on the watch and in the app. Mostly very intuitive. I’ve had issue with Bluetooth connection to my LG Sunset phone, and no connection with a Smart BT rower or bike. Although it’s indicated to keep the watch ‘on’ for connection to the phone, I find they will connect on their own if I just sit the watch next to the phone for a few minutes. In testing, I found that the step counter was off on the low side by 3 – 4 steps per 20. That’s 15 – 20%. The heart rate monitor seemed to be off, but my only comparison is the old finger and watch method. Here it seemed to be high most of the time, and at times seemed to fluctuate widely. The sleep monitor is, and can only be, for a basic idea of your sleep. I know for sure I’m waking at night, sometimes up to an hour, but the watch is registering sleep. Although I turn on heart rate monitoring when I lay down, and off when I get out of bed, the graph shows a time slot of 10PM to 10AM, with a record of sleep within that period. The start time is close enough, but the end time is way off, and so the sleep record is way off. For example, I woke and turned off the monitor and removed the watch from my wrist at 6AM, but the graph shows ‘Awake’ at 6AM and ‘Light Sleep’ and ‘Deep Sleep’ from ~6:15 to 9:42. That’s 3.5 additional hours of bliss I never had. The ‘on’ side seems pretty right, but there should be no activity record after the monitor is turned ‘off’.The app, VeryFitPro, needs a little work. I always think of the statement made to me by a project manager of a large multi-national media company when he said “Testing is overrated.” The new credo these days is to push it out to the public and let them [pay] to test it. Anyway, little things like the app display going to the top of the screen, behind the task/notifications bar, even though there is text and swipe function in that area of the app. Some words are clipped – can only see the top 2/3 of a word. On the Homepage, the sleep chart is viewable on all three tabs (Activities, Sleep, Heart Rate) under ‘My Day’.All that being said, I read issues with watches 3x this price. Just keep in mind that almost all the contenders in this market are not made for accuracy, but rather for fashion/style, to capitalize on the current craze, and capture your data. Save yourself some money and buy a basic watch like this one. It will give you enough info to fill the bill.