This is a smart watch and not a band, meaning it can receive and make phone calls as long as it is connected to the mobile phone via Bluetooth through the app. It can receive calls during a workout, which will continue to be recorded normally, but one cannot make a call even if the workout is paused. The communication is quite satisfactory, although outdoors the watch needs to be positioned between the ear and mouth.
To start the watch, it must be done through the app; therefore, one cannot use it for the first time without creating an account with Xiaomi, which will require an email address. There is no app that can record swimming activity, even though the watch is waterproof and can be used in a pool, which for me is its biggest negative – minus 1 star for that. It is also not possible to "trick" the watch into using another app to record distance during swimming. Only the ascent, as an activity, recorded ~5 meters over 50 actual meters in the pool. The only "poor" alternative is the "Free" activity option, which will only record the calories burned during the workout. Truly, perhaps the biggest disadvantage of the watch in my opinion.
Although it claims to have GNSS (Global Navigation Satellite System), which is broader than GPS (Global Positioning System), it cannot be used if the watch is not connected to the mobile phone. And I explain: a) if the distance from home to the supermarket is 1 km north and b) the distance from home to the subway is also 1 km south, if the watch is not connected to the mobile phone, it will record the same distance in both cases, but what it will not record is each route on a map. I mention this because it could record the distance in a pool in the same way, but without showing that distance on any map (in my opinion unnecessary) and force you to buy a watch at double the price just for that.
Another star off because it does not have Greek on the home screen. For example, it writes Tuesday instead of Τρίτης, even though Greek has been selected as the interface language. Also, no one can change the language through any setting without a reset (I just mention it).
Another star off because it does not have the European way of writing the date, practically in any face of the mobile. Only one pre-installed face keeps up appearances a bit, as it writes the first 3 letters of the month below the day, but only in English. All faces of the mobile (~ about 200) are free through the app, but only two at a time can be installed on the watch (small downside).
Another "loss" is that it does not have a calendar, like its bigger siblings, which I think would not require special programming and effort to include. No one can see the step count from the previous day unless connected to the mobile phone. However, one can see a graph of heart rates from previous days without syncing the watch with the mobile phone.
It has a very beautiful design, according to my preferences, while its strap, although you have to place it on yourself to fasten it, I find it really very practical, because it doesn’t have a loop that can be damaged. The change is not the easiest possible, but I don’t think anyone will do it every day, and it also seems stable. Battery life with moderate use is about a week, while I consider its price reasonable ~ around 30 euros. Also, there is no risk of accidentally pressing the button while someone is wearing the watch. Its use is mandatory, as otherwise no one can access the available applications. I think it is very practical that it has a flashlight. The weather as an application will work as long as the watch is connected to the phone and will provide a lot of information such as wind speed, temperature, pressure (of the atmosphere), sunrise and sunset, the latter accompanied by a nice graph showing its curve. It also has some applications, but I will mention the alarm clock which can work independently of the mobile. I would say that scrolling between applications is successful 8 out of 10 times, while at most with the second it will make the watch do what was selected. In conclusion: for someone who is not interested in the liquid element, does not get confused with the non-European date format and the English language on the home screen, wants to manage calls and all this at an affordable price, I consider it a good choice. Otherwise, for the same company, either the Redmi 3 (older, but same "chassis") or the 4 (a bit larger), while without calls the Band 8 is also recommended. All three of these have, among other things, a calendar and pool activities. However, they do not "fit" the same straps, which cost over 5 euros each... The evaluation concerns use < a week.