Zeplin - Collaboration app for UI designers & frontend developers
Google Docs - Create a new document and edit with others at the same time -- from your computer, phone or tablet. Get stuff done with or without an internet connection. Use Docs to edit Word files. Free from Google.
Abstract - A secure, version-controlled hub for your design files
Bit.ai - Bit is a smart real-time document collaboration platform for teams to create interactive documents, manage digital content and track document insights.
Mightytext - Send & Receive SMS Text Messages from your computer. Sync'd with your Android #
OnlyOffice Docs - OnlyOffice Docs is an effective document creation and editing platform that provides you the options to create any kind of document with the collaboration of your team from any remote location.