RingCentral - RingCentral is the leading provider of cloud-based communications and collaboration solutions for small business and enterprise companies
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Dialpad - Switch is a cloud-based phone system built for Google Apps users.
Olvid - The most secure messaging app in the world.
Aircall - Aircall is a call center software of a new generation designed for fast growing companies. Setup instantly and integrates to your CRMs
WireMin - WireMin is a private messaging tool for your most personal communications.