Khan Academy - Khan Academy offers online tools to help students learn about a variety of important school subjects. Tools include videos, practice exercises, and materials for instructors. Read more about Khan Academy.
Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
Calcohol - Need to dilute alcohol? How fast water start to boiling?
MIT App Inventor - App Inventor is a cloud-based tool, which means you can create apps for phones or tablets right in your web browser.
HappyCoding - Simplify your iOS & macOS development.
Bubble.io - Building tech is slow and expensive. Bubble is the most powerful no-code platform for creating digital products.