HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM

BuiltWith - Find out the technology behind websites

GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!

Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.

Quokka (formerly Kryptowire) - The gold standard in SAST, MAST, IAST, and more!

WhatRuns - Extension that helps you identify technologies used on any website at the click of a button.