@Rospo, no, the TMO internet app doesn't allow for the changing of connected devices name.  It's definitely an inconvenience.

It's done through the phone, not the gateway or TMo app. At least, that's how it works with Android. Works for any device using DHCP, not for static assigned IPs. On Android, use something like: Settings, Sysem, About Phone, top line is phone name, tap to edit. This sets the name for Bluetooth and WiFi.  The name you set on each phone will show up when viewing connected devices through the app. Try it.

The app is pretty bad.  I often get a spinning wheel when I tap Devices.  When I do get a list, it’s not quite complete.  My iPhone, which has its own name and is on iOS 16.5, shows up as “Apple iPhone (iOS 15)”, like the OP’s.  My Amazon Echo speakers, all of which have names, all show up as “Android.” 🤨

Despite the quirks, I have been extremely pleased with the internet service. 

   Found this on another thread.  This is for Apple products only. In each device you need to select WiFi settings and then select the “i” icon next to your network name. Toggle OFF the Private Address switch. Your connection will reboot and then the next time you check your Devices, you’ll see your device’s name. Only do this with your private network of course. ;)

@Rospo Thanks for that info.  I assume it worked for you?  I tried it, with the result of not seeing my iPhone listed at all, even after rebooting the gateway. 

 Thank you this worked perfectly 

Hey there just wanted to say that I’ve already changed the name’s on my device, named one just S24 U.  Still shows connected as the MAC address. So It doesn’t really go by the device Name .   Hope you ha ve a great day .