This app provides a drag-and-drop programming environment, mainly meant for education. It connects to a device hosting an HTTP server, which provides a definitions for valid elements of a programming language. This server will also receive the programmed functions, as an abstract syntax tree, encoded in JSON, and can execute them.
Ideal devices for this are robots equipped with sensors and a raspberry pi, to run the server. A python server, which offers a connection to the app, and executes the programs as python code, can be found here. A microcontroller version of this is in the works, so that booting into an operating system will no longer be nessecary.