The installation was helped by the comments of a review that said how the cables are inserted, but the instructions of the video do not apply because someone must first create an account on the somfy page that I found through a search.
The hub seems to have the logic of distributing the distance from the wifi.
Using it from the device, as mentioned, is probably not easy for everyone, but I like that it lights up while the application is rich in settings and I like that it uses geolocation to automatically adjust the temperature.

I bought it in 2018 and in three years the wireless connection broke. It would freeze and the connection wouldn't complete. Its disadvantages are as follows:
• When it broke, I spoke to the dealership at least 5 times before they finally told me to send it to them. It took them a week to tell me that the wireless connection had broken. Inconvenience for the consumer for no reason. The tragic thing is that they told me they have many cases like mine, which is why they were delayed. Obviously, I wasn't the only one.
• When I bought it, as well as the two times I changed the modem, it didn't connect easily. All three times, I called the dealership to finally resolve the issue. I think this is due to the inexplicably complex way and mechanism in which the wireless connection is made, meaning it has a thermostat, a "plug" that you put in an outlet, and you connect with this "plug". Out of all the wireless devices I have purchased, this is definitely the most complicated. Also, inconvenience for the consumer for no reason. There is no reason for so much wireless security for a thermostat.
• Finally, it doesn't measure the temperature correctly. Many times, there was a deviation. Unexplainably, other times there wasn't.

After a long failed love affair, I decided to get married. We met through a matchmaker, the girl had good recommendations, and after a relatively short acquaintance, we ended up getting married because that's how I see my relationship with Somfy. Specifically:
I had to replace Legrand Smarther (with a heavy heart) after many problems I had (I have written a review). The seller recommended it to me compared to Siemens RDS110. Although it didn't impress me, I decided to try it since he assured me that I could replace it if I didn't like it.
The installation is very simple, two wires (on/off) which gave me some trouble due to the small size of the thermostat, I had to squeeze them.
For the internet connection, I connected the hub and followed the instructions exactly from the manual, and in a few minutes, the application was connected to the thermostat. I should emphasize that the distance between the router-hub-Somfy is 2.5m (imagine an equilateral triangle).
Impressions:
1. The screen is small, touch-sensitive with lights that flash according to the temperature of the room until the desired temperature is reached, something like the kit it had on the hood (for the old ones). I would describe it as not so user-friendly, one has to get used to it, and it is definitely not recommended for elderly people.
2. The application is very good with a user-friendly interface, with all the parameters you need and easy weekly programming. It can detect if you have the window open (sudden temperature drop), if there is someone at home (through the mobile phone), and adjust accordingly. The good thing is that everything works perfectly.
Compared to Legrand Smarther or other thermostats I have worked with, it's like comparing Windows 10 to Windows 8, no comparison, if you work with it, you will understand the superiority of Somfy.
3. Internet connection, here I want your attention.
With Somfy, I have not had any disconnections for 1½ seasons. It does not exist, I have a new house with all the devices being smart, there is always one device that I faced a connection problem with at least once. It has never disappointed me, that's why I don't use the screen, but the application.
4. The temperature bothered me quite a bit, and after many experiments, I concluded that it is not the actual room temperature but the perceived temperature. What do I mean? When the humidity is 50-60%, then it shows the actual temperature, as the humidity increases, the perceived temperature increases, while when the humidity decreases, the actual temperature decreases. This is good because when I turn on the fireplace, I have the temperature I want to feel in the room, whereas in the past with other thermostats, the heat was excessive, higher than what I wanted, I had to lower it. Finally, it is not calibrated.
5. It does not have an on/off button, to turn off the thermostat, you set the temperature to 10 degrees. If you want to turn it off completely, you have to turn off the boiler. It is not connected to a boiler or cooling system.

In conclusion, if you want a reliable smart thermostat, I recommend it, it certainly has disadvantages, but its advantages are more.

Update 2/12/23
After 3 seasons, everything is working correctly without any problems.
As for the disconnections, I only had two, one time I restarted the router and the other time the hub.

I have bought 2 THERMOSTATS because the house is a maisonette. One of them broke and I have sent it for repair 15 days ago and they haven't responded yet. As a thermostat, it is great, but as a dealership, it is terrible, such a shame! You will hear from me again. (Eventually, the thermostat was replaced with a new one and for that, I congratulate Mr. NIKOS (warehouse keeper of KAUKA in Peristeri) who showed interest and made the change. It has many functions and parameters that can make your life easier, from GPS to understanding when you are leaving the house and lowering the heating for oil economy. It is worth the money.

In the year 2020, Somfy cannot create a standalone device but requires an intermediate Hub to connect to the network (minus one socket, while even with a Chinese smart bulb, you can control it directly from your mobile phone). The application instructions are designed for an ideal home system created by the person who made it and do not apply to old houses, etc. Personally, I replaced an old Siemens with 3 cables (all white), of which only the phase (L) and the command (NO) are needed, not the neutral (N).... you put the phase in (COM). These are not mentioned in the application and the Somfy technician told me about them. I had trouble connecting the thermostat to the network and speaking with the Somfy technician, he suggested I watch this video (https://www.youtube.com/watch?v=Wmog8PDSSvo). If there is anyone else with the same issue, they should try the following... 1. Open the GPS (otherwise it will never show your network).... Somfy probably finds it logical for some reason. 2. When you press the thermostat to wake it up, you need to set it to a high temperature for the click to be heard and the red light to turn on (not a low and blue light).... the application simply tells you to press it to see numbers! 3. Remove the thermostat from the base and keep it relatively close to the Gateway. In general, the company probably believes that customers have plenty of time to talk on the phone with their technicians, so instead of fixing the instructions, they hired helpful people (very helpful at the call center, hence the three stars, otherwise I would give a negative rating if I could)! As a device, it will show in a month, so I will come back... update After 1 year and after changing the thermostat twice because it disconnected from the network and never found it again, and after being without a thermostat for both times for a month, I returned it to the store and suggested they set it on fire and not bring it back for sale! I suggest Somfy to stick to opening and closing doors, and I think that's enough for them

The product is amazing! I noticed an immediate difference in the heating and warmth of my house! Besides being able to control everything through the app provided by Somfy for this specific product, such as house temperature and humidity, you can also remotely increase or decrease the temperature or simply create one or two weekly schedules where you can adjust it differently every day as you wish, so that the house has a standard temperature for energy saving! There are also many other settings that you can adjust within a few minutes! The most important thing is that anyone who still has one of the old analog thermostats, I recommend changing it immediately because what I noticed with my own gas boiler is that it burns at a low combustion level, while with the old one, whether there was a small or large difference in the temperature you requested compared to the one inside the house, the boiler always burned at full power! So just imagine how much money you save from this!