On Android, I downloaded Termux from the Google Play Store and ran that. I use an ASUS tablet to run TE for Home Guard FC, the instructions below should also work on any Android device (including phones).
1) Start up TE, then go back to your home page (using the 'Home' icon, not the 'Back' icon) and run Termux.
2) When the black screen comes up, type in 'netstat' and enter, and a whole big report will print out.
3) Scroll back to the top and there will be a lot of lines starting 'tcp'. Find the one where the 'Foreign Address' column starts with 'h88' and your server is the number just before the '.host'. If there is more than one take the one where the LAN: number starts with a '5'.*
See below:
So I guess Home Guard FC are on server 125...
* All the lan: numbers I've seen on PC platform start with '5' so I assume the same is true of the Android ones.