Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
BuiltWith - Find out the technology behind websites
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.
Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
RingCentral Video - Live life unlimited. Free video meetings and team messaging in one app that works the way you do.
What CMS - WhatCMS.org looks at a variety of factors within a webpage to determine what CMS a website is using.