Apps similar to PhonixPBX include Asterisk, which is free and open source. Other options are 3CX, FreeSWITCH, FreePBX and FusionPBX. In total there are seven IP PBX Systems like PhonixPBX for Linux, Mac, Windows, the web 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
3CX is a software-based, open standards IP PBX that offers complete Unified Communications, out of the box.
Offers a free trial period, after with you need to upgrade to paid subscription.
Cyprus
EU
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.
FusionPBX is an open source FreeSWITCH GUI. FusionPBX can be used as a high available single or domain based multi-tenant PBX, carrier grade switch, call center server, fax server, voip server, voicemail server, conference server, voice application server, appliance framework...
VitalPBX is a full-feature PBX (phone system) based on Linux and Asterisk. VitalPBX is extremely easy to use, fast and secure. VitalPBX is free to use, including for commercial use, with no limitations of the amount of users.
Pakistan
