lighttpd - A secure, fast, compliant, and very flexible web-server that has been optimized for high-performance environments
Postman - The Collaboration Platform for API Development
nginx - A high performance free open source web server powering busiest sites on the Internet.
Sauce Labs - Test mobile or web apps instantly across 700+ browser/OS/device platform combinations - without infrastructure setup.
Apache HTTP Server - Apache httpd has been the most popular web server on the Internet since April 1996
TestComplete - TestComplete Desktop, Web, and Mobile helps you create repeatable and accurate automated tests across multiple devices, platforms, and environments easily and quickly.