VitalPBX

VitalPBX is a full-feature PBX (phone system) based on Linux and Asterisk.

3CX Phone System

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

An open source telephony switching and private branch exchange service for Linux.

AsteriskNOW is the fastest way to get started building custom telephony solutions with Asterisk.

Cloud Telephony delivers automated telephone applications to any phone, any place, anytime.

Switch is a cloud-based phone system built for Google Apps users.

FreeSentral is a full IP PBX consisting of a Linux Distribution, an IP PBX and a Web Graphical User…

FusionPBX is an open source FreeSWITCH GUI.

Your Open Source Solution For Unified Comunnications And More…

Kamailio® (successor of former OpenSER and SER) is an open source SIP server released under…

PBX in a Flash is a PBX system based on Asterisk, FreePBX and CentOS, coming as an ISO download.

RingCentral is the leading provider of cloud-based communications and collaboration solutions for small business and enterprise companies

Starfish PBX aims to be an open source alternative to Digium’s Switchvox.

Incredible PBX is a secure and feature-rich implementation of the Asterisk® PBX.

Wazo is a unified communications platform based on Asterisk and focused on extensibility.

Private & Secure Messenger

FreePBX is a web-based open source GUI that controls and manages Asterisk (PBX).

OpenSIPS (Open SIP Server) is a mature Open Source implementation of a SIP server.