Lumicall app
Lumicall is Phone & SMS tool that is open source under the GPL-3.0-or-later license. SIP softphone with a comprehensive range of features:* ENUM dialing seamlessly checks all numbers you dial
* DNS SRV lookup keeps track of which contact email addresses are active for federated SIP
* TLS encryption of SIP messaging and both SRTP and ZRTP supported for audio stream encryption
* ICE/STUN/TURN algorithms for NAT traversal in virtually any network (based on ice4j from Jitsi)
* Push-to-talk (PTT) walkie-talkie mode allows free group chat on wifi (as long as the router supports multicast)
* Built in Ganglia agent provides an enterprise-grade monitoring solution to map wifi coverage and it's relationship with call quality
* Native x86 support