Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
Matlock Extension - Detect the Open Source libraries running on websites
BuiltWith - Find out the technology behind websites
Waves Insights - Consumer Insights SDK for Messaging Platforms
WhatRuns - Extension that helps you identify technologies used on any website at the click of a button.
DataBasic - Easy-to-use web tools for beginners