Müllkalender is a free Android app developed by sector27 GmbH under the Utilities & Tools category. It is a handy tool for residents of six cities in Germany, including Dorsten, Datteln, Marl, Oer-Erkenschwick, Schermbeck, and Raesfeld. The app provides the next trash collection dates for each street, taking into account special regulations such as holidays.

The app's version 1.1 automatically updates the collection dates, ensuring that users have the latest information every time they open it. The app also allows users to add the collection dates to their device calendar and set reminders so that they never miss a trash day again.

Müllkalender is a great solution for those who often find themselves wondering which bin to put out next. It is user-friendly and informative, making it an essential tool for those who care about keeping their city clean.