Pinned Calendar

An Android app that pins this week's Google Calendar events and to-dos to your notification shade, self-healing and fully on-device. Kotlin, Jetpack Compose, and Material You.

Overview

Pinned Calendar keeps this week's Google Calendar events and your to-dos in a single ongoing notification at the top of the Android shade. It reads the calendars already synced on your device, so there is no Google sign-in, no OAuth, and no internet permission, and your schedule never leaves the phone. The pin is self-healing: swipe it away by accident and it re-posts itself, and when you do want it gone you switch it off in the app or turn on swipe-twice-to-remove.

What I Built

A privacy-first productivity app with a testable, platform-decoupled core:

Pure-Kotlin core for windowing, day-bucketing, and content building, unit-tested and independent of Android, consumed by a thin platform layer of RemoteViews, WorkManager, and receivers.
Persistent, self-healing notification with no foreground service, a delete-intent receiver that re-posts on swipe, and Top, Normal, or Silent priority.
Local to-dos stored in DataStore that merge into the same agenda and carry forward day to day until done.
Material 3 and Material You throughout: wallpaper-based dynamic color, seed colors, AMOLED black, selectable fonts, and a theme- and accent-adaptive launcher icon.

Highlights

Reads device calendars through Android's Calendar Provider with per-calendar colors, no account or network required.
Day-grouped agenda (Today, Tomorrow, and weekday sections) with tasks shown as their own rows.
A configurable window of the next 3 days, this week, 7 days, or 14 days, with per-calendar filtering and an item cap.
Background refresh with WorkManager and a ContentObserver for instant updates, and the pin restores itself after reboots and app updates.
Offline by design: no INTERNET permission, no analytics, no accounts, and minimal permissions.

Full Write-Up

I broke down the self-healing notification, the on-device calendar reads, and the testable date math in a dedicated post: Pinned Calendar: A Self-Healing, Offline Agenda for Android.

Screenshots

Pinned Calendar's persistent notification showing the week's agenda in light mode

Pinned Calendar's persistent notification showing the week's agenda in dark mode

The Pinned Calendar settings tab with Material You cards for notifications, time window, and calendars

It is open source and MIT-licensed on GitHub, with more at pinnedcalendar.ahnafnafee.dev.

Overview

What I Built

A privacy-first productivity app with a testable, platform-decoupled core:

Pure-Kotlin core for windowing, day-bucketing, and content building, unit-tested and independent of Android, consumed by a thin platform layer of RemoteViews, WorkManager, and receivers.

Persistent, self-healing notification with no foreground service, a delete-intent receiver that re-posts on swipe, and Top, Normal, or Silent priority.

Local to-dos stored in DataStore that merge into the same agenda and carry forward day to day until done.

Material 3 and Material You throughout: wallpaper-based dynamic color, seed colors, AMOLED black, selectable fonts, and a theme- and accent-adaptive launcher icon.

Highlights

Reads device calendars through Android's Calendar Provider with per-calendar colors, no account or network required.

Day-grouped agenda (Today, Tomorrow, and weekday sections) with tasks shown as their own rows.

A configurable window of the next 3 days, this week, 7 days, or 14 days, with per-calendar filtering and an item cap.

Background refresh with WorkManager and a ContentObserver for instant updates, and the pin restores itself after reboots and app updates.

Offline by design: no INTERNET permission, no analytics, no accounts, and minimal permissions.