HOME FRONT — WARTIME HOME SCREENHOME FRONT

Prepared means unafraid. When the alert sounds, open this.

SURVIVAL MAP / SANCTUARY MAP / Evacuation drill

Survival handbook (readable offline, 10 chapters)

Plan and progress

Rebuilding wartime apps used abroad, within Japanese law and public data. The goal: from alert to refuge on one screen, even with no signal.

ModelHereStatus
Air AlertPress on alert → refuges back-calculated from the time left. JMA warnings polled every 60 s while open, with notificationsLive (J-Alert civil-protection messages have no public API, so reception is left to emergency cell broadcasts)
Home Front CommandTime left (missile 4 min / drone 60 s / quake 15 s) and only reachable sheltersLive (Japan publishes no official per-area times, so these are uniform)
Points of InvincibilityWater points, disaster bases and stay facilities, nearest firstAll 18 Yokohama wards / Tokyo's 213 water stations
Diia check-inRoom ID + passphrase, family-only status. No location; deleted after 14 daysLive
Red AlertTimeline of JMA warnings and your own records, meeting pointsLive (stored on the device)
Mamad (safe room)Home safe-room check: score rooms by windows, two walls, floor and structure; pick your best room nowLive
Diia (documents)Photos of key documents encrypted on the device only (AES-GCM); never uploadedLive
Gaza blackoutsComms-blackout kit: safety text with neighbourhood name, 171, 00000JAPAN, Bluetooth messagingLive
Russia's bus-stop sheltersNearest reinforced building or underground shown by the alert timerLive
My MDA (emergency)Location on screen (neighbourhood + coordinates) before calling 119, location SMS to family, medical ID card (device only, full-screen for paramedics), CPR beat (110/min), bleeding controlLive (no volunteer dispatch: Japan has no receiving organisation)
Self-protection, fighting back only to escapeLoud siren + strobe / SOS Morse, "run → hide → report → resist last", breaking a grip, home intrusion, self-defence and carry laws, description notesLive (no weapons, jamming or attacks on soldiers: illegal and they strip civilian protection)
Survival handbook10 chapters from the US Army's public ATP 3-50.21 and Japanese official guidance. Readable offlineLive (JSDF manuals are not public)
By-situation actionsNuclear, missile, drone, robot, soldiers/occupation, air strikes/strafing; how Israel, Ukraine, Russia and Gaza prepareLive
Offline mapArea map tiles, refuges and water points saved to the deviceLive
Missile sheltersTokyo 5,113 and Yokohama 162 geocodedMore Kanagawa cities next
Android app (Japanese name: 戦争対策, "War Preparedness")App that opens on this page, split into five tabs: Alert, Protect, SOS, Map, Familyv1.2 built; Play release pending review
Background pushAlerts even with the app closedUnder study

Sources: GSI Japan, JMA, Yokohama City open data, Tokyo Metropolitan Government. This tool does not replace official instructions.