Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
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.
Invision - Prototyping and collaboration for design teams
Gmelius - Gmelius is the first collaboration platform designed for G Suite and your company's daily tools.
Sketch - Professional digital design for Mac.
Boomerang for Outlook - Boomerang for Outlook offers email productivity tools to track, schedule and send mails at the right time.