Sdui is the digital platform for secure communication and organisation in schools. With the web-based app, students, teachers and parents can interact with each other easier than ever before: Any important information around school life, such as timetables, parent letters and announcements can be communicated easily via the app. The development of Sdui began for a school project in 2015, 2018 the Sdui GmbH has officially been founded. Currently, the company employs around 30 people and has reached many hundreds of schools. The app has been awarded several times and is used as GDPR-compliant standard for school communication by cities and communities all across Germany.