Quora Writing Sessions - The popular Q&A platform launches their version of AMA's
Sketch Talk - A community for Sketch users of all skill levels
Boost - Boost is an e-commerce for mobile, where users can generate hashtags for products and instantly sell and buyers can tweet to make a purchase
SketchCasts - A weekly screencast, all about how to use Sketch
Wisdo - Learn from people who’ve been there
Sketch 101 by Designlab - Learn Sketch in this free course w/ downloadable templates