TaskDav

Tasks, notes, and a calendar that sync over CalDAV — or stay on the device.

TaskDav is a free and open-source Android app for people who want their planning data on a server they control (Radicale, Nextcloud, Baïkal, …), without Google Play Services, analytics, or ads. It works fine next to DAVx⁵ on the same account.

Home-screen widgets for notes, tasks, today’s events, and a week/month agenda.

Why TaskDav?

Most “productivity” apps want a proprietary cloud. TaskDav speaks plain CalDAV:

• Your server, your data — credentials stay encrypted on the phone; nothing is sent to the TaskDav authors
• Local-only mode — use it without any account until you are ready to sync
• Works with the FOSS stack — designed to coexist with DAVx⁵ and other CalDAV clients
• No Play Services — suitable for GrapheneOS, LineageOS, and F-Droid-style installs

Features

• Offline-first tasks (VTODO), notes (VJOURNAL), and events (VEVENT) with Room + WorkManager sync
• Nested tasks and nestable categories (RELATED-TO / X-TASKDAV-KIND:CATEGORY)
• Tags (CATEGORIES), due dates, priorities, and optional linked calendar events
• Weekly recurrence for events (RRULE)
• Home dashboard: overdue, due today, today’s agenda, recent notes
• Calendar views (day / week / month / year / list)
• Themes from a single brand color; UI in English, Spanish, and Italian
• Home-screen widgets for today, week/month agenda, tasks, and notes (plus a compact agenda size)
• Share tasks, events, or notes as text + .ics; export collections
• Optional mirror / import with the phone calendar (CalendarContract)
• Handles “add event” / ICS intents so TaskDav can be a calendar target

Install

From source (debug)

export JAVA_HOME=$(/usr/libexec/java_home -v 21)   # JDK 17+
export ANDROID_HOME=~/Library/Android/sdk

./gradlew assembleDebug
adb install -r app/build/outputs/apk/debug/app-debug.apk

Stores

TaskDav is intended for F-Droid and similar free-software catalogs. Store listing text and screenshots live under fastlane/metadata/android/ (EN / ES / IT). A draft fdroiddata recipe is in metadata/app.taskdav.yml — copy it into an fdroiddata fork as metadata/app.taskdav.yml and open a merge request. Links will be added here once the package is published.

Release build (minified)

./gradlew assembleRelease -PuseDebugKeystore
# APK: app/build/outputs/apk/release/app-release.apk

Release uses R8 minify + resource shrinking. F-Droid builds from source and signs with their own key.

Quick start

1. Open the app → finish onboarding (or skip) — you land in local-only mode with an on-device calendar.
2. To sync: Settings → Syncing → CalDAV → base URL, username, password → Save & discover → enable collections → sync.
3. Optional: keep DAVx⁵ for contacts/calendars; TaskDav talks to the server itself for tasks, notes, and its own events.

Radicale collection example

curl -u USER:PASS -X MKCOL 'https://caldav.example/USER/tasks/' --data \
'<?xml version="1.0" encoding="UTF-8" ?>
<create xmlns="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav" xmlns:I="http://apple.com/ns/ical/">
  <set>
    <prop>
      <resourcetype>
        <collection />
        <C:calendar />
      </resourcetype>
      <C:supported-calendar-component-set>
        <C:comp name="VEVENT" />
        <C:comp name="VTODO" />
        <C:comp name="VJOURNAL" />
      </C:supported-calendar-component-set>
      <displayname>Tasks</displayname>
      <I:calendar-color>#2B6A4FFF</I:calendar-color>
    </prop>
  </set>
</create>'

Use a base URL like https://host:5232/USER/ in TaskDav.

Privacy

• Account credentials live in encrypted preferences on the device
• Tasks, notes, and events live in a local database and are sent only to the CalDAV server you configure
• No analytics, crash-reporting SDKs, ads, or Google Play Services
• Uninstall or clear app data to remove the local copy

See Settings → Privacy in the app for the full notice.

Architecture (short)

Area	Role
caldav/	OkHttp + dav4jvm, PROPFIND/REPORT/PUT/DELETE, ical4j
data/	Room, encrypted account prefs, locale / appearance
domain/	Task tree, repository, sync orchestration
sync/	WorkManager periodic + reconnect push
ui/	Home, Calendar, Tasks, Notes, Settings
widget/	Glance home-screen widgets

Requirements

• Android 8.0+ (API 26)
• Optional: a CalDAV server advertising VTODO (and optionally VEVENT / VJOURNAL)
• JDK 17+ to build

Limitations

• No DAVx⁵ ContentProvider integration (TaskDav syncs over CalDAV itself)
• Recurring events: series edits only (no single-occurrence exceptions yet)
• Recurring tasks are not edited in-app (existing RRULEs may be preserved on rewrite when possible)

Contributing

Pull requests and issues are welcome. See CONTRIBUTING.md for the branch model and PR checklist.

Short version

Branch	Use for
main	Stable / releases
develop	Next release integration
feature/…, fix/…	Your work → PR into develop

git checkout develop
git pull
git checkout -b feature/my-change
# … commit …
# open a PR targeting develop

Useful entry points: app/src/main/java/app/taskdav/, string catalogs under app/src/main/res/values*/strings.xml.

Debug builds include a demo seeder for screenshots:

adb shell am broadcast -n app.taskdav/.debug.DemoSeedReceiver -a app.taskdav.debug.SEED_DEMO
./scripts/capture-screenshots.sh

License

TaskDav is free software under the GNU General Public License v3.0.

Third-party libraries keep their own licenses — see Settings → Credits in the app.