Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
XO Hosted PBX - Hosted PBX is a scalable UC solution that uses cloud technology to integrate HD voice & data services, mobility, along with advanced calling
WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.
VoIP.ms - VoIP.ms is a VoIP origination and termination tool.
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Mitel - Business Communications and Collaboration