SendHub - Get a business phone system on your smartphone and computer. We provide professional, affordable sms, text, and voice solutions in an easy to use system. 14-day free trial.
Asterisk - An open source telephony switching and private branch exchange service for Linux.
Mobiniti - Mobiniti offers a mobile marketing platform for clients to invite customers to engage with their brand through SMS via their mobile phone.
Wazo.io - The UCaaS Platform Built for MSPs
CallHub - Predictive Call Center, Voice and Text Broadcasting app
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.