Google Voice vs Signal

Dialpad

Contact Center as a Service

Viber

Messengers

RingCentral

A cloud-based business communications solution that include message, video, phone, and contact center services

Aircall

Cloud-based call center software for customer-centric teams

Skype

Communication solution with voice, video, messaging, and file transfer

WhatsApp

Messaging app by facebook

Telegram

Cloud-Based Messaging App with Focus on Speed and Security

Viber

Messengers

Discord

A modern service for group voice, video, and text communication

Slack

A cloud-based platform for team communication and collaboration