Offline Bluetooth mesh
A messenger that doesn't need the internet.
PIING Nearby builds a mesh out of the PIING phones around you. Your message hops phone to phone over Bluetooth until it reaches your friend, sealed so nobody in between can read it.
How the mesh works
- Swap keys once, onlineOpen a chat with a friend while you have signal. PIING exchanges the keys that keep Nearby messages private.
- Signal drops, Nearby startsPIING finds other PIING phones over Bluetooth automatically.
- Up to 5 hopsYour message is passed phone to phone; each phone extends the range by roughly 10 to 50 metres.
- Delivered, with a tickOnly your friend can open it. Phones in between can't read it.
Encryption details: Nearby messages are encrypted, but without the post-quantum protection used for online chats. See Security.
Works with no signal
- Messages, check-ins and your last known placeWith no signal, PIING can send "I'm OK" check-ins and, every few minutes, your last known place to your safety circle, phone to phone over Bluetooth.
- Carried until someone has signalAny PIING phone that picks it up carries it, sealed, and uploads it the moment it gets signal. Your circle then gets it. PIING's server only ever sees scrambled data it can't read.
- SOS goes firstAn SOS jumps the queue, goes further (up to 8 phones), and is uploaded first by whoever gets signal. Your circle is asked "Are you OK?".
- BatteryNearby looks for phones less often when nobody is around and pauses in the background. Expedition mode, for trips, saves more and wakes when you start moving.
Limits. It only works phone to phone over Bluetooth, between PIING phones with Nearby on. Range depends on your surroundings (walls, crowds, terrain) and on how many PIING phones are around; out on a hill or at sea there may be nobody to pass it on. Messages are encrypted end to end between phones; the design has not been independently reviewed yet. PIING never replaces emergency services and never calls them for you. Call 999 or 112 if any phone line works, and carry a personal locator beacon or satellite messenger in remote places.
Questions
What is a Bluetooth mesh messenger?
An app that sends messages directly between nearby phones over Bluetooth, relaying them through other phones to reach people further away, with no mobile network or Wi-Fi.
Does PIING Nearby need Wi-Fi or mobile data?
No. It uses Bluetooth, phone to phone.
Can the phones relaying my message read it?
No. Messages are end-to-end encrypted, so only the people in the chat can read them.
Which devices does it work on?
PIING for iPhone. Both people need PIING installed.