Telephone
Telephone is a VoIP program which allows you to make phone calls over the internet.
20 Alternatives To Telephone
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3CX Phone System
3CXPhone is a free VoIP phone available for Windows, iPhone or any Android based smart phone such…
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Acrobits Softphone
Acrobits Softphone, an app for entry into the world of SIP.
Asterisk
An open source telephony switching and private branch exchange service for Linux.
Blink
Blink is a team and employee app, with a Feed, Chat and Hub (for documents, links, files).
Bria
VoIP and video calling, messaging and presence - all from your computer desktop with the award-winning Bria 5 softphone client.
Ekiga
Ekiga (formely known as GnomeMeeting) is an open source VoIP and video conferencing application for…
Jitsi
Open-source video calling and chat platform.
LINE
LINE is a Japanese proprietary application for instant messaging on smartphones and PCs.
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Nimbuzz
Get the latest, headlines, breaking, regional news fast.
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Phoner
Softphone for VoIP, CAPI und TAPI.
Signal
Fast, simple & secure messaging. Privacy that fits in your pocket.
Starfish PBX
Starfish PBX aims to be an open source alternative to Digium’s Switchvox.
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Vodia Networks
Vodia Phone app is a free add-on for your Vodia PBX that lets you connect to your account on your…
Wazo
Wazo is a unified communications platform based on Asterisk and focused on extensibility.
Wire
Private & Secure Messenger
X-Lite
The X-Lite softphone from CounterPath. Try out our fully-loaded Bria desktop client including voice and video call, messaging and presence or download X-Lite for try to test SIP softphone features.
YakYak
Desktop client for Google Hangouts
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Zoiper
Cross-platform VoIP softphone dialer for SIP and IAX systems
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freepbx
FreePBX is a web-based open source GUI that controls and manages Asterisk (PBX).
tSIP
tomeko.net/software: SIP client for Windows.