3CXPhone

3CXPhone is a free VoIP phone available for Windows, iPhone or any Android based smart phone.

3CXPhone can be obtained from the 3CX website.

Installing 3CX VoIP Phone is easy and only takes a few minutes.

Click on Set Up/Configure Account. Click on New.

Account name is a useful reference for this account on your computer
Caller ID should be your name. It is what other VoIP phones will see as the caller.
Extension should be the login ID for your extension provided to you in your welcome email
ID should be set to the same as Extension
Password will be provided to you in your welcome email. It might also be called SIP Secret

Ensure I am in the office - local IP is selected, and enter the hostname or IP address as provided to you in your welcome email.

Click Advanced settings toward the bottom of your SIP Account settings window to set advanced options.

Configuration