Introduction
Islamic Corner was an Android utility app combining Quranic Surah reading, location-aware Azaan prayer time alerts, and a digital Tasbeeh counter in a single lightweight application. I designed and built the entire app with a focus on offline reliability — all core features had to work without network access, and Azaan alerts had to fire reliably even when the device was in deep sleep.
The Challenge & Solution
The hardest problem was reliable Azaan notification delivery. Android aggressively restricts background processes to conserve battery, and a standard background service would be killed before the next prayer time, causing silent alert failures — the worst possible outcome for an app users depend on for religious observance. The solution was AlarmManager with WAKE_FROM_IDLE flags, which schedules OS-level alarms that wake the device from deep sleep at the exact prayer time and fire the notification without requiring a persistent background service. Prayer times were calculated on-device using astronomical formulae with the device’s GPS coordinates, so accurate alerts required no network call and worked in areas without connectivity. This made the app fully self-contained: the Quran text was bundled as local assets, the Tasbeeh counter persisted to SharedPreferences, and prayer time calculation ran entirely offline.
Technologies & Architecture
- Java: Standard Android development language at the time of this project, providing full access to all Android SDK APIs including AlarmManager and location services needed for this app’s core functionality.
- AlarmManager (WAKE_FROM_IDLE): OS-level alarm scheduling that woke the device from deep sleep to fire prayer time notifications — the only reliable mechanism for time-critical background notifications on Android without a persistent foreground service.
- Android Jetpack: Navigation components and lifecycle-aware architecture for the Surah reader and Tasbeeh counter UI, ensuring state was preserved correctly across activity recreation and configuration changes.
- GPS / Location API: Used to determine the user’s coordinates for on-device prayer time calculation using standard Islamic astronomical formulae — no network request needed, alerts worked anywhere with a GPS fix.
Key Highlights
- Prayer times & alerts
- Bookmarks
- Lightweight UI
Impact
The AlarmManager-based approach delivered reliable Azaan alerts even on battery-optimised devices in deep sleep — solving the most critical reliability requirement for an app used daily for religious observance. Full offline functionality made the app usable without any network dependency, keeping it lightweight and reliable across all network conditions.