Slack Overflow - A programmer's best friend, now in Slack.
Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
GitCommands - An interactive reference tool for Git commands
Microsoft Teams - Microsoft Teams provides the enterprise-level security, compliance and management features you expect from Office 365, including broad support for compliance standards, and eDiscovery and legal hold for channels, chats, and files.
GitHub + Slack Integration - Full visibility into your GitHub projects right inside Slack
RingCentral Video - Live life unlimited. Free video meetings and team messaging in one app that works the way you do.