Heurix.io - Heurix is a free heuristic evaluation tool that helps you work out how to improve your website.
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
UX Companion - A handy glossary of UX theories, tools and principles (iOS)
Lumar - (Previously DeepCrawl) Hosted SEO spider to analyze and find problems with websites.
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.
Website Checker Tech - WebsiteChecker.Tech is SaaS tool that detects SEO and availability issues of your website, making it easier for you to fix them.