
Description: IETester is a free utility that allows you to test websites in different versions of Internet Explorer on the same computer. It simulates IE 5.5 to IE 11 without needing multiple virtual machines.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: BrowserStack is a cross-browser testing tool that allows you to test your website or app across various browsers and devices. It provides an online testing environment and a large range of browsers and operating systems.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API