Responsinator - Designed to test responsive websites on different devices.
UXsniff - Track user behavior on your website and improve conversions with UXsniff: the user experience watchdog that looks out for you.
SlideRule UX Design Path - Curriculum of Online Courses To Learn UX Design
Rage Grade by FullStory - Benchmark your customer frustration
BareMetrics - SaaS Analytics for Stripe
Toole - Search for and discover online tools