It is quite useful and necessary if you want to control your network remotely. Otherwise, the alternative is to set up a computer as a server and keep it permanently on.
The main menu is simple and easy. You can see the network topology schematically, all your devices separately, the clients, the network traffic, and make settings for internet, LAN, wireless, VPN, reboot, etc... and all this remotely.
If you want to use it properly and fully customize the network, you need basic knowledge, or otherwise you can ask ChatGPT and it will tell you step by step what to do. I would suggest the initial setup be done from a computer via IP and not from the mobile app.
It is PoE, so if you have a PoE switch, you don't need a separate power supply. I have it connected to a TL-SG2008P switch, and I have an ER605 router and 2 Access Points connected to it.
One more thing about the version. I ended up ordering it from two stores that claimed it was v2.0 but sent me v1.0. From what I learned, v2.0 came out for a while due to a microchip shortage, but then they reverted to the original, which is exactly the same (possibly better is 1.0). So it doesn't matter which one you get.