Daily.co for Intercom - Free video calls & screen shares embedded in Intercom
Onesheet CRM - The Simple CRM for Google Sheets
Pluot Communications - Big-screen video conferencing for startups
Followup.cc - FollowUp for email is a lightweight productivity suite that keeps your conversations and tasks from slipping through the cracks. Set perfectly timed reminders that arrive at the top of your inbox, right when you need them.
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.
Freshsales CRM - A full-fledged CRM for high-velocity sales teams.