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!
Balsamiq - Balsamiq. Rapid, effective and fun wireframing software.
UserZoom - Test, measure, and monitor UX with our cost-effective all-in-one platform. UserZoom is a cloud-based solution for online usability testing.
Invision - Prototyping and collaboration for design teams
Validately - Validately is a user feedback platform to test demand and usability on a clickable prototype or live feature.
Zeplin - Collaboration app for UI designers & frontend developers