Lydia - Lydia lets you use your card whatever you need to pay, even a friend.
Alcamy - Free, open self-learning platform. Learn & teach anything.
Noodlio - The marketplace for app development
Stacks - A bookshelf for your online courses
Xtendify - Marketplace for Open Source CMS and Frameworks.
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!