
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: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: MicroSIP is an open source SIP softphone and instant messenger for making VoIP calls and sending IMs over the Internet. It supports standard SIP accounts from various providers and has features like audio/video calling, chat, presence, and more.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API