The setup for the Groundwire App is pretty simple. Once you have the App installed on your device touch the three dots at the top right hand side of the screen and touch accounts. There is a green plus sign at the bottom of the screen, touch that to add an account. Touch New SIP Account. In the title section name it whatever you like. I named mine AmateurWire.
In the username section put your extension number, in the password section put your password and in the domain section put the servers domain like pbx1-wv.amateurwire.org:5060
That should be all you need to do for the app. If you have any issues connecting to the server you could also try the IP address in the domain section which is 18.104.22.168:5060
Beyond that if you have issues you may have the password wrong or another issue so go to the website and submit a support ticket, catch me on Discord in the #support channel or email me at firstname.lastname@example.org and I will check our end to make sure there is no issues on our side.