If you're looking for an app to help you prepare for your 4th-grade Physics and Chemistry class, then "cours de physique chimie 4eme" might be just what you need. This free app by moro app provides easy access to the best Physics and Chemistry courses at any time.

The app is divided into three main chapters: Energy, Movement, and Matter. Each chapter is further divided into several sub-chapters that cover topics such as the conservation of energy, production of electrical energy, interaction and forces, and the structure and composition of the universe. The app also includes a PDF version of the course, exercises, and a book for further reading.

Overall, "cours de physique chimie 4eme" is an excellent app for anyone looking to improve their knowledge of Physics and Chemistry. The app is easy to use, the content is well-organized, and it's completely free. The only downside is that the app doesn't provide any way to contact the developer or provide feedback.