Although as a proposition it is very good, it ultimately has an issue with charging. Both times it got stuck while charging. The first time it didn't turn on again and I returned it. The next time, it turned on but remained stuck on the battery as shown in the picture. While we used it, it was quite reliable, but as an implementation, it is poor. I do not recommend it, you will waste your time and the child will be disappointed.
However, both times I did not have a problem with the return. The first time it was replaced and the second time I received a refund. The purchase was made through skroutz

3 stars because it seems very satisfactory and when you hold it in your hands you say it's worth it. So I got it as a gift for my nephew, he was very happy but after the first charge it simply doesn't charge and doesn't turn on, so now I have to search and find where the service is.
My favorite.

To use and synchronize it, a SIM card with both voice and data is necessary, something that is not clarified before purchasing it. So afterwards, it is useless because it does not synchronize with WiFi. The battery does not last even a day and the Chinese application that you will install on your phone is completely user-unfriendly and most of the time it does not load. Very expensive for what it offers.

One star, because it can't get any worse....
After 1 month, the speaker breaks and the child can't hear anything, the GPS signal is laughable at times. The child is next to me and the signal is 15 km away...
After 2 months, the screen stopped working, so the child couldn't even answer.
And when I sent a message to the company, I never received a reply.
These are for 2 watches, one for my son and one for my niece, and they both experienced the same issues within a few weeks of each other....
Simply unreliable.
If you want it for a couple of months, it's fine.

In 2 days, the watch broke, it didn't even hear the child and I could hear it from the next room. What a waste of money.

After two days of use, the watch stopped working. It was replaced and the new watch stopped working on the first day

I have bought 2, one pink and one blue. The blue one got stuck after 2 days, I sent it back and they told me it had moisture (ridiculous!!!). After a lot of hassle, they sent me another one! Meanwhile, the pink one also got stuck after one day. I put it on the radiator all night and it worked!!! The new blue one arrived and the next day it got stuck again!!! 3 out of 3!!! Since the radiator is not working now, I put it in rice, which as we know absorbs moisture, and it worked again!!! As for its functionality, it is perfect, you know where your child is at all times, but I recommend getting a different model because this one is very sensitive. Also, the battery lasts for 1 day, maybe even less, even when not in use.

The setup took us quite a long time. The application it connects to is Chinese, with a terrible translation into Greek. As soon as we inserted the sim and mb, we realized that the GPS had a kilometer deviation and the heart rate and step measurement were not functioning. We returned it. I would not buy it again. If you are interested in GPS, do not choose it.

Easy operation of the application... complete parental control from their mobile phone.
Accuracy in GPS, which was the most important for us, we tested it on the same day. The SOS button is useful, it sends a message with the exact location of the child when pressed.
Easy to use by an 8-year-old child. It speaks clearly and can hear us as well.
We got it to communicate with him during his school trips and activities.
It requires a activated SIM card with talk time and MB before inserting it into the watch, and it is very important to remove the card's PIN.

It is a very good watch with an incredibly powerful speaker when talking on the phone, which you can lower and increase the volume. One downside for me is that it is not waterproof and I would like the messages I send to my child to not be limited to only 15 characters, you can't write much. Despite all this, if you want it to monitor your child and have contact with phones, it is great and worth its money!