If you’re using an Ubuntu Phone, you’ll be glad to learn that you can now make VoIP (Voice over IP) calls no matter where you are thanks to the work done by two Open Source software developers to port the Linphone app to the Ubuntu Touch mobile operating system currently maintained by the UBports community. With the Linphone app installed on your Ubuntu Phone, you can create a SIP (Session Initiation Protocol) account from Linphone.org to call another SIP or eNum client free of charge, as well as to call regular phone numbers, which requires a SIP account with credit. Linphone also lets you log in with your existing SIP account.