BroApp - Your Clever Relationship Wingman
Courseroot - Biggest online course database on the web
Giggle - Giggle is a graphical frontend for the git content tracker (think of gitk on GTK+).
Airschool - Airschool is a live-streaming educational platform with engagement and monetization tools to help anyone start teaching online. It can be finance, business, wellness, meditation, branding, marketing; in short, anything you want!
Alcamy - Free, open self-learning platform. Learn & teach anything.
Content Marketing Stack - A curated directory of content marketing resources