Guilded - Find, manage, and challenge gaming teams

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!

Quizzly - Quizzly is a platform, for learning purposes, It gives full ability to create a small to large quizzes and to play them with your friends.

Userbrain - Easy, fast, and affordable user testing for websites and prototypes.

Houseparty - Brining empathy to online communication.

UserTest.io - User testing made simple. High-quality, affordable user testing solutions from real users, here in the UK. Improve your usability!