RingCentral - RingCentral is the leading provider of cloud-based communications and collaboration solutions for small business and enterprise companies
MightyCall - Virtual phone system that lets you run your business from anywhere.
Dialpad - Switch is a cloud-based phone system built for Google Apps users.
Line2 - Line2 adds a second phone number or complete cloud business phone system to smartphones & computers that's robust yet affordable. Buy online or get a custom quote.
Aircall - Aircall is a call center software of a new generation designed for fast growing companies. Setup instantly and integrates to your CRMs
JustCall - The Cloud Phone System of choice for modern sales and support teams. We help end clueless conversations by adding context to every call.