Heurix.io - Heurix is a free heuristic evaluation tool that helps you work out how to improve your website.
Screaming Frog - Screaming Frog is search engine marketing agency offering search engine optimisation and pay-per-click advertising services.
Heurio - Do website reviews faster. Heurio eliminates the administration process and lets you focus on creating value in a collaborative and user-friendly way. Perfect for heuristic evaluation, design and development review, bug report, QA testing and more.
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
UX Companion - A handy glossary of UX theories, tools and principles (iOS)
SEOmator - SEO website analysis & audit tool