Zmanim calculations
KosherJava is vendored locally and wrapped by ZmanimHelper so builds are not blocked by flaky dependency fetches.
Android alarm clock · KosherJava
Alarms that move with the halachic day.
Zmanim Alarm computes zmanim for the user’s location and arms Android alarms against those shifting times, with daily refresh, reboot recovery, tones, debug logs, a tester bench, and a next-zman home-screen widget.
Coming soon to Google PlayToday in Chicago
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Before netz20 min before sunrise
ONSof zman shemadaily recalculated
ONBuilt like an alarm app has to be built.
Exact alarm workflow
Alarm slots, Android Clock intents, daily exact refresh, foreground service, and boot receiver keep scheduled alarms current.
Device verification
Debug logs, log viewer, Run Worker action, tester activity, and multiple fire mechanisms exist because wake-up reliability must be tested on device.
Reliability details
00:05 refresh
DailyAlarmScheduler and DailyAlarmService reload slots and call the shared alarm refresh logic.
Reboot recovery
BootReceiver re-arms the schedule after the device restarts.
Tone selection
TonePickerActivity and ToneHelper manage default and chosen alarm sounds.
Widget surface
NextZmanWidget gives a home-screen readout for the next zman.
The hard part is not drawing a clock
Alarm intent layer
AlarmHelper builds SET and DISMISS intents for Android Clock, because the app needs the operating system’s alarm behavior, not a decorative timer.
Foreground work
DailyAlarmService runs the refresh as a foreground service for scheduled and manual worker runs.
Battery reality
BatteryOptimizationHelper exists because exact alarm reliability depends on device settings as much as calculation correctness.
All Zmanim view
ZmanimListActivity exposes the broader daily zmanim list beyond the alarm cards.
Debug bench
AlarmTesterActivity and seven scheduling methods make it possible to isolate how a device actually fires.
Android subsystems
MainActivity
Main alarm-card screen and footer controls.
AlarmSlotAdapter
RecyclerView adapter for saved zmanim alarm slots.
TonePickerActivity
Ringtone selection for each alarm slot.
ZmanimListActivity
Full daily zmanim list beyond the alarm cards.