Mobbin - Latest mobile design patterns & elements library
Heurix.io - Heurix is a free heuristic evaluation tool that helps you work out how to improve your website.
pttrns - iPhone and iPad user interface patterns
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.
Page Flows - User flow design inspiration for mobile & desktop
UX Companion - A handy glossary of UX theories, tools and principles (iOS)