SafiWorkshop allows you to design, test, debug, and deploy advanced process flow applications (like IVRs) from a single, unified development environment. For database work, it includes a fully featured SQL query editor. SafiWorkshop also includes some Asterisk PBX specific features like an audio prompt editor.
DeforaOS Phone is a GTK+ application that has an interchangeable telephony backend, complete with call, contact, and message management. With its backends for GSM modems, it can be used as the telephony application on phones including the Openmoko Freerunner, Nokia N900, and some HTC phones running custom Linux distributions, and as a tethering application that provides Internet access to a desktop computer. Support for VoIP protocols is under development, with a backend based on the sofia-sip library.