Description: CSipSimple is an open source SIP client for Android that allows you to make VoIP calls over Wi-Fi or mobile data. It supports common SIP features like call transfer, call forwarding, call waiting, 3-way conferencing, etc.
Type: software
Pricing: Open Source
Description: Tango is a free and open source, cross-platform program for video calling and instant messaging using Voice over IP. It offers encryption, group conversations, file transfers, customizable user profiles, and other features.
Type: software
Pricing: Open Source