App Launch Checklist - Planning tool for launching your app successfully
SketchCasts - A weekly screencast, all about how to use Sketch
ASO Tools by AppFollow - Tools for App Store Optimization in App Store & Google Play
GoRails - Ruby on Rails screencasts for Web Developers
ConversionChecklist.org - A 41 point checklist to make your website convert better
Sketch Talk - A community for Sketch users of all skill levels