iOS + Android · Launching early 2027
ColdBoot turns your phone into a field kit. Maps, compass, Morse, sun times, pantry tracking and a survival library, all in one app, and nearly all of it works with no signal at all.
Six modules · one kit
Grouped the way you'd reach for them in the field. Most tools work in airplane mode from the first launch. Maps and the seasonal outlook just need one download while you have signal.
The basics, always within reach.
Tools: Flashlight · Notepad · Checklist · Voice Log · Unit Conversion · Device Status
Find your way without a cell tower.
Tools: Map · Map Library · Star Map · Grid Reference
A survival library you can search with no signal.
Tools: Health · Survival Guide · Weather · Tools & Knots · Emergency
Get a signal out when you can't make a call.
Tools: Morse Code · NATO Phonetic · Digital Whistle · Radio Frequencies · Ground-to-Air Signals · Decibel Meter
Know what you have, and how long it lasts.
Tools: Pantry · Inventory · Depletion Calculator · Barter Estimator · Emergency Planner · Scenario Cards
Read the sky, the pressure and the season.
Tools: Sun Times · Lunar Cycles · Sky Events · Barometric Pressure · Seasonal Outlook
A closer look
Comms · Morse Code
Type a message and ColdBoot flashes it with your phone's light, with an optional tone. Tap in dots and dashes to decode a reply, and train your ear with a trainer that plays Morse for you to name, from single letters up to full sentences.
See the full Morse code chartReference
Nearly 100 guides across health, emergencies, tools and knots, weather and survival. Each gives clear steps, what not to do and the warning signs to watch for. Search them with no signal, and bookmark the ones you'll want fast.
Earth · Sky Events
Eclipses, solstices, equinoxes and supermoons for the year ahead, plus when Venus, Mars, Jupiter and Saturn rise where you are. It is all worked out on the phone from planetary models, so it's there without a connection.
Prepper · Inventory
Track supplies by where you keep them, at home, in the car or anywhere you add, with quantities, units and expiry dates. The Depletion Calculator then gives a rough estimate of how long your pantry and inventory would last for the people you're planning for.