diff --git a/README.md b/README.md
index fdc1a69..0410754 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,47 @@
 [![CI](https://github.com/de-men/amlich/actions/workflows/ci.yml/badge.svg)](https://github.com/de-men/amlich/actions/workflows/ci.yml)
 [![codecov](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/thaihuynhxyz/750c80dac4c020472e8510f5ca8c8b7a/raw/coverage.json)](https://github.com/de-men/amlich/actions/workflows/ci.yml)
 
-[A web app](https://amlich.demen.org) that converts between solar (Gregorian) and Vietnamese lunar dates, built with [Flutter for web](https://flutter.dev/web).
+A Vietnamese lunar calendar ([Âm Lịch](https://amlich.demen.org)) web app built with [Flutter](https://flutter.dev/web).
+
+## Features
+
+- Solar (Gregorian) and Lunar date conversion
+- Moon phase visualization for each day
+- Can Chi (Heavenly Stems & Earthly Branches) for day, month, and year
+- Auspicious hours (Giờ Hoàng Đạo) with zodiac icons
+- Month calendar view with lunar day numbers
+- Solar/Lunar focus toggle
+- Dark (celestial) and Light theme
+- Swipe gestures for day and month navigation
+
+## Add Vietnamese Lunar Calendar to Google Calendar
+
+You can subscribe to the Vietnamese lunar calendar to see lunar dates directly in your Google Calendar:
+
+1. Open [Google Calendar](https://calendar.google.com)
+2. Click **+** next to "Other calendars" in the left sidebar
+3. Select **From URL**
+4. Paste this URL:
+
+```
+https://calendar.google.com/calendar/ical/demen.org_4jc7p02lkoire319rabglmfifo%40group.calendar.google.com/public/basic.ics
+```
+
+5. Click **Add calendar**
+
+Or click this link to add it directly:
+
+[Add to Google Calendar](https://calendar.google.com/calendar/r?cid=demen.org_4jc7p02lkoire319rabglmfifo@group.calendar.google.com)
+
+## URL Parameters
+
+You can open the app with a specific date using the `date` query parameter:
+
+```
+https://amlich.demen.org/?date=10-02-2024
+```
+
+Format: `dd-MM-yyyy` (day-month-year)
 
 ## Getting Started
 
@@ -14,6 +54,14 @@ flutter run -d chrome
 
 ## Deployment
 
+Deployment is automated via GitHub Actions. Every push to `master` builds and deploys to [amlich.demen.org](https://amlich.demen.org).
+
+To build manually:
+
 ```bash
 flutter build web
 ```
+
+## License
+
+[BSD](LICENSE)