The whole interface is intuitive and easy to learn: each part of the game can be designed using visual editors. The objects editor is used to create the objects of the game, the scene editor help you to build the levels of your game and the events editor allows to give life to the whole game without programming.

GDevelop is available in many languages and even community can help in translations.

A new doc is improving for gd5 that is nice for beginners and after that you can learn more from examples. Also, gd4 wiki is still there.

Prebuilt behaviors can be added to objects. This is a very efficient way to add a physics engine or make a platformer game. Lots of behaviors are included, from the most advanced (Physics, platformer, top-down movement) to really simple one (like the behavior to destroy objects when outside the screen or the one to drag objects with mouse or touch).
And you still have full controls over your game as behaviors can be modified using the events!

The engine includes pathfinding, physics engine, multitouch support, custom hitboxes, platformer engine, tiled maps, multiple layers and cameras out of the box.

All of these features can be used without programming knowledge, using the visual editors.

The plugin SDK is open source, so if you want to extend it, you can.

No need for coding using this system which is clear and powerful: events are composed of conditions and actions. Actions are launched when conditions are fulfilled.
This is a very friendly way of making games and is still efficient for advanced usage, contrary to most other "block"/"drag'n'drop" systems.

GDevelop's runtime libraries are MIT licensed. It can be used freely for projects of any type and there are no royalties associated with publishing games developed with GDevelop.