Clock — a debloated, e-ink-first alarm app for the Bigme HiBreak Pro

A ~253 KB replacement for the 10.2 MB OEM alarm app, built for one specific phone: an e-ink Android 14 device where every animation is a defect and every wasted megabyte is a byte the panel does not have to repaint.

Package	com.ilyaas.einkclock
Device	Bigme HiBreak (HiBreak Pro), Android 14 / SDK 34, arm64-v8a, e-ink 824×1648 @ 300 dpi
Stack	Kotlin, classic framework Activity/Views. No AndroidX, no Compose, no coroutines, no third-party libraries
APK	253 KB, one classes.dex, zero native libraries, resources.arsc 7.5 KB, English only
Tests	21 JVM unit tests (./gradlew :app:testDebugUnitTest)

Why I wanted this

I wake up to a burst of alarms, not one. 8:00, 8:05, 8:10, 8:20 — an alarm every 5, 10 or 15 minutes for an hour, because one alarm is easy to sleep through and the next one is the one that actually gets me up. That works exactly once: the morning I wake up on my own, or the first alarm does its job, I am still being shouted at by every remaining alarm in the set, and dismissing them one screen at a time at 8:03 is the opposite of a good morning.

What I wanted was one button on the ringing screen: I'm awake — meaning this whole run of alarms is done, cancel the rest of them for today, and bring them back tomorrow. Not "snooze everything", not "skip one", not a per-alarm "delete after use". The rest of the burst is not a reminder; it is the same wake-up.

No alarm app I could find does that. AOSP DeskClock, LineageOS, GrapheneOS and the FOSS clocks all dismiss exactly one instance (the survey in clock-audit/). Fossify Clock, the closest thing to a base, implements "skip" by clearing today's weekday bit with an upstream TODO calling it a hack — which is wrong for a single-weekday alarm. So the feature had to live in an app I controlled anyway.

Three more things pushed me to write my own rather than patch someone else's:

• It is an e-ink phone. The HiBreak Pro's panel is the slowest part of every interaction: anything that animates, ripples, slides or repaints once a second is a defect, and a clock that redraws 60 times a second to show the same minute is pure waste. The screen should change when the information changes and not one frame more.
• The stock app is a brick I cannot fix. 10.2 MB, 8.7 MB of dex at 94.5 % of the single-dex 64 K method-reference limit, 1.7 MB of native libraries for three ABIs the phone cannot run, ~85 locales and 3.7 MB of resource table, 58 MB of PSS — and it is platform-signed with sharedUserId=android.uid.system on a phone with no root, so it cannot be patched, re-signed or replaced. It can only be disabled.
• The small things mattered too. I wanted the world clocks the stock app shows, with the cities I pick instead of Berlin/Mumbai/Auckland forever, and an alarm editor that is not a maze of Save / Cancel / OK / Delete where nothing tells you which one commits your change.

So: my own app, ~1/40th the size, no animation, no AndroidX, no Compose, no coroutines, no third-party libraries, and one feature at the centre of it that nothing else has — a wake-up burst that goes away in one press, per day only, with Undo if I was too quick.

Why the stock app could not do it

com.android.deskclock is an OEM-forked AOSP DeskClock, platform-signed and sharedUserId="android.uid.system", sitting at 94.5 % of the single-dex 64 K method-reference limit. Adding a feature would need multidex surgery and the platform signing key, on a device with no root. And the batch dismiss does not exist upstream at all: dismiss() deletes one instance and returns.

The one vendor hook it exposes, com.android.provider.AlarmProvider, is a dud — query/insert/update/delete all return nothing and call("start_service") only re-runs boot init. It cannot be used to read or cancel alarms. Android has no public API for app A to enumerate or cancel app B's alarms, so "I'm awake" has to live inside whichever app owns the alarm database.

Disabled, not modified:

adb shell pm disable-user --user 0 com.android.deskclock   # → new state: disabled-user
adb shell pm enable com.android.deskclock                  # revert

What it does

Four text-only tabs — CLOCK · ALARM · STOPWATCH · TIMER — in pure black on pure white, with no ripple, no elevation, no transition and no per-second repaint.

The headline: "I'm awake"

Alarms are usually a burst: 8:00, 8:05, 8:10, 8:20 — the same wake-up, four times. When you are already up, one press must silence the rest of the burst:

1. The ringing screen shows the current time, the alarm's label and scheduled time, the scheduled time again if snoozed, and three buttons: I'm awake (full width), Pause and Cancel (half width each). Back and volume keys never dismiss it.
2. I'm awake dismisses this instance and then walks the alarm set forward in a chain: starting at now, it takes the next enabled alarm within window minutes of the previous one, skips it, and repeats. A burst with 5-, 10- or 15-minute gaps therefore disappears as one unit instead of stopping after the first window.
3. Skips are rows in alarm_skip(alarm_id, date) — never a mutated repeat mask and never enabled = 0. Tomorrow is normal by construction, one-shot victims are disabled instead, and a 10-second Undo deletes today's rows and reschedules.
4. The window is configurable: 5 / 10 / 15 minutes (Settings).

Measured on the phone: the 8:00 alarm fired for real at 08:00:00.205, the ring screen was up in +110 ms, and pressing I'm awake produced Skipped 8:05 AM, 8:10 AM, 8:20 AM with three alarm_skip rows for today, every row still enabled=1 with repeat_mask=127, and every registered trigger moved to tomorrow. An 8:40 alarm — outside the chain — stayed armed. dumpsys alarm and the raw database pull are in TESTING.md.

Everything else

• Alarm list — one bordered card per alarm: HH:MM at 56 sp (24- or 12-hour per the system setting, dimmed to 50 % gray when off), label + repeat summary (Every day, Weekdays, Mon, Tue, Wed, Once, plus skipped today), and a framework Switch on the right. Tap to edit, long-press for Edit / Delete.
• Editing without ambiguity — + asks for the time first and creates the alarm; the detail screen writes every change immediately (time, label, days, snooze, vibrate, ringtone). There is no Save button to hunt for: only Done to leave and Delete (confirmed) to remove.
• World clock — bordered cards with city, N hours ahead / Tomorrow, N hours ahead, and the local time. Default selection matches the stock app (Berlin · Mumbai · Auckland), + Add city picks from ~34 zones.
• Stopwatch — MM:SS.hh in mono, 10 Hz while running, 0 Hz while stopped, surviving process death.
• Timers — N simultaneous timers, presets 1m · 5m · 10m · 15m · 30m · 1h, pause/resume, +1 min, a plain 4 dp progress bar, and a "Timers up" screen.
• Intent API — SET_ALARM, SET_TIMER, SHOW_ALARMS, SHOW_TIMERS, DISMISS_ALARM, DISMISS_TIMER, SNOOZE_ALARM (with the stock manifest's com.android.alarm.permission.SET_ALARM alias guard).
• Scheduling — setAlarmClock() per alarm (so SystemUI shows the next alarm and Doze leaves it alone), exact alarms for timers, directBootAware receiver and service, alarms and prefs in device-protected storage (/data/user_de/0/…), and re-registration on boot, locked boot, time set, timezone change and app update.

Build and install

# build (JDK 17-21, Android SDK with platform 35)
./gradlew :app:assembleDebug
./gradlew :app:testDebugUnitTest

# install + make it the alarm app (non-interactive)
scripts/install.sh                       # adb install, grant notifications, disable the stock clock

# put the phone back
scripts/revert.sh                        # re-enable the stock clock, uninstall Clock

There is no ALARM_CLOCK role on this ROM, so making Clock the default is: disable the stock app (the script does it) and pick Clock once in the SET_ALARM chooser. Verify with:

adb shell cmd package resolve-activity --brief -a android.intent.action.SHOW_ALARMS
# com.ilyaas.einkclock/.api.HandleApiActivity

Two Android 14 permissions matter and are nudged on first run:

• Display over other apps (SYSTEM_ALERT_WINDOW) — without it, Android 14 blocks a background app from raising the ring screen; the alarm would only post a notification while the phone is unlocked. scripts/install.sh grants it over adb; Settings shows the status and a deep link.
• Battery optimization exemption — otherwise Doze can delay alarms.

What was measured, and where it misses

Full raw output is in TESTING.md. The honest summary:

Gate	Target	Result
APK ≤ 600 KB	600 KB	253 KB ✅
One dex, no .so, en-only	yes	yes ✅
Cold start ≤ 300 ms	300 ms	median 304 ms (287–324 in the final series) — faster than the stock app (median 376 ms) and Settings (461 ms), but only just at the line ❌/✅
PSS ≤ 25 MB	25 MB	49–59 MB (stock: 58–65 MB) ❌ — the shared framework floor alone is ~38 MB on this ROM
0 idle frames	0	0 frames / 30 s, 0–1 / 60 s (one minute-boundary repaint, no seconds, nothing periodic) ✅
T0–T8 acceptance	pass	pass, with two documented adaptations (see TESTING.md)

Layout

app/src/main/java/com/ilyaas/einkclock/
  data/       SQLite (device-protected), models, prefs, world-clock catalogue
  alarm/      next-trigger math, scheduler, receivers, ringing service, ring actions, timers
  ui/         MainActivity (tab shell), one view class per tab, ring/edit/settings screens
  api/        alarm clock intent API
  debug/      debug-only test hooks (test ring, alarm factory, DB dump) — never in release
app/src/test/ JVM unit tests for the scheduling math and the "I'm awake" selector
clock-audit/  the original audit this app was built from (measurements, stock APK, screenshots)
docs/         screenshots used by this README and TESTING.md