How do I use tasks and advanced features like sub-tasks with DAVx⁵?

DAVx⁵ stores all task information in the database (content provider) of a supported app. Currently, these task apps are supported:

  • jtx Board (developed in collaboration with DAVx⁵)
  • (actively developed by a third party)
  • OpenTasks (doesn't seem to be developed anymore)

jtx Board – Journals, Notes and Tasks

jtx Board supports tracking and managing journals, notes and tasks in a single app.

You can link these components with each other. It is aimed to be your personal tracker for everything you want to organize. jtx Board is the first and only app on any mobile operating system that supports the VJOURNAL standard which is used to sync journals and notes to your server over CalDAV. For tasks sync, the app uses the VTODO. The app has been developed in close collaboration with us (DAVx⁵).

jtx Board supports:

  • journals (for tracking stuff with a date of happening, like protocols, meeting minutes, or also simply as your diary if you use it personally) – stored as VJOURNAL¹
  • notes (simple notes taking to keep track of ideas and other simple stuff) – stored as VJOURNAL¹
  • tasks (with features like subtasks, recurring tasks and – usable as a grocery list for example) – stored as VTODO

Hint: you may need to create a new collection with support for notes / journals  in DAVx5 → CalDAV tab → Create collection so that you can use the full potential of jtx Board. Not all servers support the creation of new collections.

¹ Not all servers may support VJOURNAL collections. – Open-source To-Do Lists & Reminders is a powerful open-source to-do list & reminder app.

There's a list of supported features at, which include:

  • tasks (VTODO) with due dates,
  • sub-tasks,
  • recurring tasks.


OpenTasks doesn't seem to be developed anymore, so we recommend to use one of the alternatives above.

OpenTasks can store (content provider) and edit (UI) tasks.

However, the UI currently doesn't implement all things which are supported by the content provider, like subtasks, recurring tasks, and task categories. To use these advanced features, you need an app like aCalendar+ in addition to OpenTasks.