Prosty Kalendarz

Most phone calendars are overloaded: banners, "smart" suggestions, ads and views you have to click through just to see a single day. I wanted the opposite — a calendar that simply shows my events in a clean, legible layout and lets me add an entry in a few seconds. I also wanted my data to stay safe and portable — not trapped in yet another app's private database that's hard to get back out of, but kept so I can reach it from any device and never lose it when I change phones.

I wrote the app natively in Kotlin and Jetpack Compose, with a Material 3 interface — the whole UI declaratively. I built five views (Year, Month, Week, Day, Schedule) on shared logic backed by java.time, switched with a pill selector at the top. Instead of the system date dialogs I added a custom wheel-style date and time picker (WheelPicker) and Material-style option sheets. Rather than keeping events in the app's own private database, I backed them with Android's system calendar provider (CalendarContract) — which lets them sync with Google Calendar and gives them a free cloud backup, while I/O runs on coroutines off the main thread and the view refreshes on returning to the app. Local reminders are handled by AlarmManager with exact alarms and notifications. Firebase (Firestore and Auth) is scaffolded for optional cloud, but deliberately switched off.

I got exactly what I wanted: a fast, clean Android calendar where adding an event takes seconds — with the reassurance that my data is safe, backed up in the background to Google Calendar. Five views cover every way of looking at time — from a glance at a whole year to a "what's next" list — and the absence of accounts, ads and needless features means nothing gets in the way — the app just does its job. It's a personal product, written from scratch and maintained for my own daily use.