Selenium - Selenium automates browsers. That's it! What you do with that power is entirely up to you. Primarily, it is for automating web applications for testing purposes, but is certainly not limited to just that.
Screenster - 10x faster UI testing without a line of code.
Phantomjs - PhantomJS is a headless browser that works hand in hand with Selenium to help developers more efficiently test their sites and apps.
Robot framework - Robot Framework is a generic test automation framework for acceptance testing and acceptance...
Cypress.io - Slow, difficult and unreliable testing for anything that runs in a browser. Install Cypress in seconds and take the pain out of front-end testing.
TestComplete - TestComplete Desktop, Web, and Mobile helps you create repeatable and accurate automated tests across multiple devices, platforms, and environments easily and quickly.