Google Voice - Google Voice gives you one number for all your phones, voicemail organized in an email format, free...

Ameyo - Ameyo is a powerful and highly flexible IP-based contact center software that lets you have a personalized interaction with every customer across multiple channels, thereby driving customer engagement to a level par excellence.

VoIP.ms - VoIP.ms is a VoIP origination and termination tool.

Aircall - Aircall is a call center software of a new generation designed for fast growing companies. Setup instantly and integrates to your CRMs

Mitel - Business Communications and Collaboration

Five9 - Five9 provides cloud-based call center software for sales, marketing and support.