Apllon is an online modeling editor written in React. It offers an easy to use and lightweight experience to learn UML and other notations in an interactive environment. It runs as standalone version on https://apollon.ase.in.tum.de offering a collaborative modeling experience without accounts. It is also integrated into Artemis to enable modeling exercises. Students create models, tutors assess those models and provide feedback which students can then see in order to improve their modeling skills. In this thesis, Apollon should be enhanced with new features such as an improved live collaboration, new diagram types, and an improved experience when assessing UML models.