BLE Emergency-Mesh

Notfall-Mesh carries text messages, voice messages, pictures, small files and locations without internet, without a mobile network and without servers – purely over Bluetooth, directly from device to device.

Important: this is not an official app of any authority or rescue service, and it is no substitute for the emergency services. As long as a mobile or landline network is reachable, call 112 or your local emergency number. The app is for anywhere without a connection — not only emergencies: a large-scale power cut, but equally hiking and camping, remote areas, festivals and large events, or an overloaded mobile network.

HOW IT WORKS

Every device running the app is sender, receiver and bridge at once. A single Bluetooth link spans only a few metres – but every message is handed on from device to device. A chain of devices can carry a message across long distances, entirely without a network. If nobody is in range, the message waits on the device and moves on at the next encounter.

ENCRYPTED

Direct messages are end-to-end encrypted. Devices that merely relay a message can neither read it nor tell who it is for. Your identity is created on the device at first start and never leaves it.

NO ACCOUNTS, NO SERVERS

No registration, no phone number, no e-mail. There is no server that messages go to. Everything stays on your device. No ads, no trackers, no analytics.

About the internet permission: the app uses the internet in exactly one place – downloading a map package, and only when you tap a region. Messages travel over Bluetooth without exception. If you would rather avoid even that, download the map file in a browser and import it.

FINDING YOUR WAY WITHOUT A NETWORK

Offline maps for all 16 German federal states, Germany as a whole and nine neighbouring countries – download once beforehand, then use them without any connection. Plus a place index built into the app: over half a million place names down to hamlets, and around 60,000 postcodes. No search request ever leaves the device. A built-in compass shows direction and distance to a received location – without a map and without a network.

FEATURES

• Text messages, voice messages, pictures, small files and GPS location
• Offline maps, search by place name or postcode, coordinate entry
• Compass for taking a bearing on a received location
• A public emergency channel where strangers in range can reach each other
• Your own channels for groups — entry by QR code only, optionally with a password as well
• Joining and leaving shown in the history, with name and time
• Public channels for meeting points that anyone can enter through the name
• Direct chats with end-to-end encryption
• Contacts via QR code, with a verifiable safety number
• SOS message with an alarm tone, relayed with priority
• Reactions, replies, forwarding and disappearing messages
• A short text alongside pictures, files, voice messages and locations
• Empty the relay store: drop other people’s packets whenever you want
• Long range over Bluetooth 5, where the device supports it
• Quick replies for the sentences you need again and again
• App lock, encrypted storage, panic wipe
• A new identity if your keys fall into the wrong hands
• A second device on the same identity, if you switch it on
• Frugal mode: an emergency brake if the network fills up with attachments
• Interface in German and English
• Privacy policy and terms in full inside the app – readable offline too

THE LIMITS OF THIS APP

Whether a message arrives depends solely on whether enough devices running this app are in range. There is no delivery guarantee. The more people use it, the denser the network becomes. Attachments are deliberately kept small so they do not block the airtime that calls for help need in an emergency. Use at your own risk.

A non-commercial project.

Recent changes:
A retired phone on permanent power becomes a fixed bridge: it carries other people’s messages onward and closes a gap nobody else would close.

Mark such a device as a bridge in your contacts — it gets its own tab, showing when it was last in range. If it stays silent for more than a day, the home screen tells you. “Check bridge” shows its signal strength continuously, so you can find its best spot.


Bugfix: Maps now offline available.