Linphone
Real-time communication·linphone.org
Linphone is an open-source softphone providing VoIP calling, video conferencing, and instant messaging, developed by Belledonne Communications since 2001. It is available for desktop and mobile platforms (with a web version coming), and supports SIP-based telephony, HD audio/video codecs, group conferencing, and end-to-end encryption including post-quantum cryptography. The product also offers an SDK (Liblinphone) and server suite (Flexisip) for developers and organizations to build custom communication solutions, plus white-label and enterprise licensing options.
What it's for
Features 20
- Auto-answer for call centers
- Automatic call relay on network change (WiFi to 3G/4G)
- Blind and assisted call transfer
- Call recording (audio and video) with in-app playback
- Contact synchronization via LDAP and CardDAV
- Dynamic media stream adaptation to network conditions
- End-to-end encryption (SRTP, SRTP-DTLS, ZRTP)
- Ephemeral messages
- Forward Error Correction (FEC)
- Full-screen video up to 1080p
- Group video conferencing up to 50 participants via SFU server
- HD audio/video calls with Opus, AV1, H265, H264 codecs
- Instant messaging with group chats, file sharing, reactions, voice messages
- Multiple simultaneous calls with hold and waiting music
- Post-quantum encryption (Cristals-Kyber)
- Push notifications via Firebase and APNs
- Remote configuration via QR code or link
- Screen sharing
- Software/hardware echo cancellation
- SSO authentication via OpenID Connect and OAuth 2.0
At a glance
Integrations
Complianceself-reported
Resources
Pricing
Enterprise licensing, white-labeling, server installation, support contracts, and custom development are all quote-based; pricing is available on request.
Described as usable for free by individual users; app downloadable free of charge.
Pricing available only via personalized quote ('devis personnalisé'); no numeric pricing stated.