Postman - The Collaboration Platform for API Development
UserTesting.com - Usability testing has never been easier. Get videos of real people speaking their thoughts as they use websites, mobile apps, prototypes and more!
Sauce Labs - Test mobile or web apps instantly across 700+ browser/OS/device platform combinations - without infrastructure setup.
Userbrain - Easy, fast, and affordable user testing for websites and prototypes.
TestComplete - TestComplete Desktop, Web, and Mobile helps you create repeatable and accurate automated tests across multiple devices, platforms, and environments easily and quickly.
userinput.io - Get on-demand feedback for your app, website or idea. Learn how to improve by hearing real opinions.