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.
Apache JMeter - Apache JMeter™.
Ranorex - Ranorex is a GUI test automation framework for testing of desktop, web-based and mobile applications.
TestComplete - TestComplete Desktop, Web, and Mobile helps you create repeatable and accurate automated tests across multiple devices, platforms, and environments easily and quickly.
locust - An open source load testing tool written in Python.
Cucumber - Cucumber is a BDD tool for specification of application features and user scenarios in plain text.