How it works.

Your sky, listened to.

Every aircraft announces itself as it flies: where it is, how high, what it is called. All day, our server listens for the ones that cross your sky.

Your sky becomes a single drawing, published at sunrise and sunset, or at whichever moments you choose. The drawing is made on our server, not on the frame — the frame's only job is to hang it up.

The frame always speaks first.

Most connected devices keep a door open so their maker can push things to them. A FlightPortrait has no door. The frame wakes, calls out over an encrypted connection, asks "is there a new drawing for me?", hangs up, and goes back to sleep. The server can answer; it can never call.

This is not a setting that could be flipped later. It is the shape of the system: the frame runs no server, keeps no port open, and accepts no incoming connection of any kind.

Asleep almost all the time.

Between drawings the frame is in a deep sleep with its radio off — not idle, not listening, off. It wakes for its editions, stays connected for less than a minute, and sleeps again. That is how it runs for months on a charge, and it means that for all but a few minutes a day there is nothing to connect to at all.

What actually travels.

When the frame calls, the conversation is small enough to write down in full.

The frame sends

Which drawing it currently shows, its battery level, its signal strength, and its firmware version. That is the whole list. The frame doesn't know your name, your account, or your address — none of that is ever stored on it.

The frame receives

The drawing, the time to wake up next, and — occasionally — a firmware update, which the frame checks byte by byte and refuses to run unless it verifies. One thing no server can ever change is which server the frame talks to: only hands on the frame itself can set that.

Your sky, not your address.

To know which planes crossed your sky, we need a rough center — and rough is exactly what we keep. If you use your phone's position during setup, the app and the server both round it before anything is stored: the coarse center, a place label, and your timezone. What we hold points to a neighbourhood, not to a doorstep.

Bluetooth for setup, then silence.

The one exception to "the frame only calls out" lasts a few minutes, once: setup. The frame shows a code on its own glass, your phone scans it, and the two talk over an encrypted Bluetooth session to hand over your Wi-Fi details. When setup ends, Bluetooth switches off and stays off. A factory reset wipes those details and starts the frame over as a stranger.

Don't take our word for it.

The frame's firmware is open source, and the protocol it speaks is published in full — every request, every field, byte by byte. If you'd rather not talk to our server at all, you can point your frame at your own: it is a supported, documented path, not a hack.

Questions we haven't answered here? Write to [email protected] — the people who built it read every message.