Asterisk - An open source telephony switching and private branch exchange service for Linux.
E-goi - Email Marketing companies, SMS Marketing, software email marketing.
FreeSWITCH - FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications.
Octopush - Octopush is a company providing technology-based communication solutions, including SMS, Web solutions, and Email APIs.
FusionPBX - FusionPBX is an open source FreeSWITCH GUI.
SendSMSGate - ✅Send SMS Bulk and 📨📨📨 Service SMS and Viber ads all over the world. 💰Cheap rices, round-the-clock support and direct contracts with mobile operators.