Fire Boltt INVINCIBLE 1.39" AMOLED 454x454 Bluetooth Calling Smartwatch ALWAYS ON, 100 Sports Modes, 8GB for 1500+ Songs, Play Music Without Phone on TWS, Spo2 & Heart Tracking

Positives first:1. The watch is big - a bit too big (in my case it covers my entire wrist).2. The user interface is cool and fast.3. There's a selectable watch face for every age group.4. Step count, o2 level and heart rate can easily be verified and seem to be reasonably accurate. Can't comment about other data (sleep pattern) as I have no way of verifying it.The Negatives:1. The strap is short - I have to use the last hole in the strap.2. Strap quality - not so great.3. Watch is non-Android which means it pairs only with its own custom app and no other.4. The app is functional but is missing a very important feature that even cheaper smartwatches have - custom watch face. There is simply no way to add a custom watch face.I haven't yet tried making phone calls /synching contacts or playing music etc.Watch faces:There are two types of watch faces:(a) selectable, 100, high-resolution watch faces and(b), 20 low resolution, minimal display watch faces.You have a choice between analog and digital type watch faces.Whichever high-resolution watch face you select, it is displayed for exactly 30 seconds (unless you tap one of the two buttons). After 30 seconds, the selected low resolution watch face is displayed for a pre-selectable time duration ranging from few seconds to always on. The low resolution watch face is dimmed and displays minimal information.There is NO option for CUSTOM WATCH FACE - (even if you connect it to the app). On some websites they claim custom watch face option is available via 'Da Fit' app. That information is wrong. The Da Fit app does not connect or sync with this watch. In any case, given that high res watch faces are displayed for only 30 seconds, it is the low res watch faces that are really important.The usb cable can be used to charge or connect to the pc for transfer of music or recordings only. You cannot access any other folder in the watch. So, no, you cannot insert your own custom-made watch face or insert a .vcf file (contact list).The usb magnetic charger cable connects smoothly but have to be careful not to touch/move the watch while charging else the cable will easily disconnect.When the idle watch face is displaying, the information on step count is not updated on the display in real time however, it does get recorded in the background. So, if you tap a button and 'wake up' the watch, it will update the step count/heart rate etc.All in all, a good buy. I recommend you also buy an additional charger cable and keep in your vehicle. You might also want to consider a metal strap.Cheers!

It's been 45 days since I've purchased this watch. I can speak in detail with each element below. I was user of Mi Band 2,4, Honor band 5 and bingo smartwatch. So most of my review have much comparison with previous bands and smartwatchDisplay (4/5)Amoled display is sharp and crisp. I can easily read the message notifications from distance. Keeping ambient sensor make it more live with auto brightness adjustment. Bezels are bit thick but if you keep a dark wall paper it doesn't matter.Design and build (4/5)This Smartwatch looks premium with its solid build quality of the frame. But the strap is bit cheaper side. I've bought a button type strap, which is more comfortable than stock strap.Notifications(2/5)This is the most annoying part of this smartwatch. I've found slight delay in receiving call notifications, but the worst part is, even after I rejected the call in mobile, call notifications continue for some time, there no button to stop the vibration. It's bit frustrating to get such kind of non-sync notifications. App notifications are good, but the message content comes first and then sender name, they could've used sender name and message in a single notification scren.Battery life (4/5)It comes 2 days if you use phone mode for receiving calls through smartwatch. It was expected. But the battery life is amazing if you keep local mode, it comes around 5-7 days. You still receiving all call notifications and app messages in local mode, couldn't lift/reject the calls in local mode.Speaker and Microphone Quality (4/5)Sound is upper side of this smartwatch. Its like a mini 2W bluetooth speaker. But the microphone quality is mediocre. I've tried speak calls with it, I can hear voice clearly, but my friend couldn't listen me clearly(when I was outside) but its fine inside in a room.Apps and Gestures (4/5)It has 100 Sports modes, but I use only 2-3 of them. I couldn't find accurate result like other premium watches as it lacks of GPS, but its better than other cheaper smartwatches. Sleep tracking interface is good. Mobile app is user friendly but not better than Mi Fit. I use music gestures during driving, but it's available for only local storage here, not while playing through Bluetooth. Heart rate and Spo2 is almost accurate with my Spo2 finger device. I like the calculator, voice recorder and timer. It's really comes handy.That's it!! Final verdict, if you need premium watch with budget price. You can go for it. If you don't need a receiving calls through it and need accurate fitness tracking, I recommend amazfit GTS2 mini instead.