AbtoVoIPClient vs Sona UC

ABTO Software's VoIP SIP softphone. Can be used to call sip numbers and landline numbers (if sip provider has this option). Features: voice calls; video calls; text chat (based on SIP MESSAGE request); works with all popual SIP servers, including Asterisk/FreeSwitch; make direct calls between clients without SIP server; allows to use UDP/TCP/TLS protocols for SIP transport; ability to make secure calls using SRTP/ZRTP; supports STUN/ICE; IPv6 support; CallKit - native incoming call UI and system integration of VoIP calls; 2 simultaneous calls; call conferencing; attended transfer.

Sona UC is a VoIP Mobile Client coordinated with Sona UC PBXs that makes your iOS mobile phone an office extension and links you and your colleagues and customers anywhere anytime. Make and receive calls through corporate phone network to slash call costs and enhance efficiency with consistent in-office experience. Key Capabilities - Make and receive enterprise VoIP calls over your Wi-Fi or mobile data networks to lower mobile voice charges - One number reach to conceal your personal mobile phone number and ensure unified corporate identity - Set up flexible ring strategy for Linkus and the desktop phone - Select different outbound routes for different destinations (local/long-distance/international, etc.) - Corporate directory integration with lookup and visual status indicator (available/unavailable/busy) - Configurable PBX features including Call Transfer, Call Forwarding, Call Waiting, DND, and Ring Timeout - Support Push Notifications to alert users of incoming calls while conserving energy Main Features Call Forwarding Call History Call Route Selection Call Transfer Call Waiting Contact Management Corporate Directory Do Not Disturb Extension Status Hold & Resume Native Contacts Integration One Touch Recording Outbound Route Selection PUSH Notification Ring Strategy Selection Speed Dial/Favorite Voicemail Specifications iOS Requirement: iOS 11.0 or higher Network: 2G/3G/4G or Wi-Fi Protocol: SIP FRC2361 Codec: iLBC/u-law/a-law/G722/G729 Network Protocol: TCP/IP/UDP, RTP/SRTP/RTCP, HTTP/HTTPS DTMF: Inband, RFC4733 (RFC2833), Info