SFLPhone: modern VoIP client for the Linux desktop

I was keeping an eye once in a while on the promising SFLPhone project, developped by the Savoir-faire Linux folks.

A slightly outdated screenshot I took (back in June, when I first wrote the draft for this blog post), since I’m too lazy to take new ones:


I’m using Callcentric as an SIP provider and Twinkle was the only Linux client (well, except x-lite) that seemed to work with it. However, Twinkle has the following problems:

  • Not very open/friendly/vividly maintained. This is my subjective view. A project that has no public bugtracker, public version control repository, and an author that does not respond to emails (I sent a few of them over the last two years), is, to me, an unfriendly project.
  • QT 3. Ewww. I can bear with that, but I much prefer GTK+ applications. SFLPhone has both a GTK+ and a QT interface.
  • Does not work well with PulseAudio
  • Complex (follows the KDE approach of maximum configurability), which is not necessarily bad for something like VoIP, however
  • Weird bits of German appearing in the GUI, poor/incomplete French translation… which I can’t fix since the author never replied.
  • A huge gaping User Interface the size of a hallway
  • Terrible icons: what’s up with having smileys everywhere? They all look alike!

But generally, Twinkle works and is stable, which is sadly much more than every other VoIP client I tried out there on the Linux desktop. I was just looking for something better-integrated (especially with PulseAudio) and for which I could contribute without feeling like my efforts were going into /dev/null.

I found out that SFLPhone improved a lot in recent times and decided to give the daily builds a shot (because the 0.9.5 release does not work with callcentric). I was amazed at how well it worked. While there are some details to polish here and there (I filed around 44 bugs since june), making and receiving calls with callcentric works quite well.


And here’s where the awesome starts: it is designed with PulseAudio in mind. That means that it [supposedly] mutes the other applications when you are receiving a call (well, it used to, at least). I shot a video of me calling my computer (using a regular landline phone), and the computer automagically handled the call by muting Rhythmbox. This, my friends, is the kind of cracktastic shit I’ve been dreaming of.


There are still many issues left to fix, but it mostly works. I use it frequently to record important calls, for example.


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