Apps similar to 3CX include Asterisk, which is free and open source. Other options are Teliqon, Thirdlane Connect, YakYak and FreeSWITCH. There's no shortage of IP PBX Systems like 3CX, with more than 25 alternatives for Linux, Windows, the web, Mac and Android.
Asterisk is an open source framework for building communications applications. Asterisk turns an ordinary computer into a communications server. Asterisk powers IP PBX systems, VoIP gateways, conference servers and other custom solutions.
Canada
Teliqon is a Global Cloud Communications Platform combining Cloud PBX, UCaaS, CPaaS, business messaging, virtual phone numbers, and contact center solutions in one system.
Estonia
EU
Thirdlane Connect is a versatile collaboration tool that combines messaging, voice, video, and app integration into a cohesive and efficient experience on any platform.
United States
FreeSWITCH is a scalable open source cross-platform telephony platform designed to route and interconnect popular communication protocols using audio, video, text or any other form of media. It was created in 2006 to fill the void left by proprietary commercial solutions.
FreePBX is a web-based open source GUI (graphical user interface) that controls and manages Asterisk (PBX), an open source communication server.
Thirdlane® Multi Tenant PBX Platform is a reliable, cost-effective Unified Communications software widely used by MSPs, UCaaS providers, resellers and enterprises around the World.
United States
Yate is a softswitch (concept of separating the network hardware from network software).
Wazo is mainly an IPBX that provides communication services such audio, video, and instant messaging based on the use of standard network technologies such as the TCP/IP protocol. It is interoperable with most market telephony systems and gives users access to flexible and...
Instant messaging with voice and video options, live group video chat for up to 10 participants, public and private rooms, interest communities, mobile and desktop access, user-created rooms, moderation tools, and options for anonymous participation.
United States
Thirdlane® Business Phone System stands as an advanced IP PBX and Unified Communications solution, designed for both on-premises and cloud deployment.
United States
Kamailio® (successor of former OpenSER and SER) is an open source SIP server released under GPL, able to handle thousands of call setups per second. Among features: asynchronous TCP, UDP and SCTP, secure communication via TLS for VoIP (voice, video); WebSocket support for...
