Inspired by trello and the open source alternative wekan I added some functionallity to support kanban-like boards in my life-tracking application.
I got also some inspiration by the deck plugin of nextcloud and github project boards.

Whith the boards module users can create boards and add other users to the board. In the board view it is possible to create different stacks and add cards to the stacks.
Users can add labels with colors to the board. Users, labels, due dates and descriptions can be assigned to cards.
The description can contain simple markdown which is rendered with simpleMDE.

Users can subscribe to daily reminder mails for due cards.