Apps similar to Ozeki Phone Systems include Asterisk, which is free and open source. Other options are 3CX, FreeSWITCH, Yate - Yet Another Telephony Engine and Wazo. You can choose from more than 10 IP PBX Systems like Ozeki Phone Systems for Linux, Windows, Mac, 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.
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...
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...
Spreed is the worldwide unified web conferencing service offering integrated web and telephone conferencing. It is based on Flash Player. Free service includes 3 attendees and max 1.5h meetings. Single events or monthly service can be purchased.
GermanyEU
XiVO is an IP-PBX, a unified communications platform that connects phones on a local or private network with other networks such as public landlines and mobile telephones.
FranceEU
VoipSwitch is a SoftSwitch System with routing and billing, with SIP protocol support (in older versions also H323).
The MiRTA PBX is an interface written in PHP using Mysql as backend to manage a multitenant PBX built over the Asterisk Open Source PBX. An easy to use interface allows you to manage one or more Asterisk PBX in a multi tenant, load sharing and high availability configuration.
The main purpose of cloud telephony is connecting with the customers for providing your services support. IVR is the software which is used for the cloud telephony.
United Kingdom