Telephone (application)

Telephone is a softphone for macOS developed by 64 Characters. It uses Session Initiation Protocol for communication. Telephone is distributed as free software under the GPL-3.0-or-later license.

Telephone

Developer(s)	64 Characters
Stable release	1.6 / June 29, 2022; 2 years ago (2022-06-29)
Written in	Objective-C, Swift
Operating system	macOS
Available in	English, German, Russian
License	2016: GPL-3.0-or-later[1] 2008: BSD-3-Clause[2]
Website	www.64characters.com/telephone

Audio codecs

• Speex/8000 (narrowband), Speex/16000 (wideband), and Speex/32000 (ultra-wideband)
• Opus
• G.711 family codec (PCMA, PCMU)
• G.722
• iLBC
• GSM