Wylmi normally opens your door over the network: the lock controller talks to our servers over its own WiFi or LTE. The Bluetooth backup covers the rare moment the controller loses that connection.
How the backup works
If the controller can’t reach our servers on its own, a nearby phone running Wylmi bridges it back online over Bluetooth, lending its own internet connection. You tap open in the app as usual; the command goes to our servers, which route it to the controller through that bridge. There’s nothing to switch on — it just works when a phone is nearby.
Is it secure?
Yes — and it never asks you to trust the phone. Over Bluetooth, the phone is only a proxy: it relays a direct TLS tunnel between the controller and our servers and can’t read or change what passes through it.
- Every open is authorized by our servers, never by the device itself.
- The controller holds no secret that could trigger an unauthorized open. Its only secret lets it connect to our API — and that alone can’t open anything.
So there’s nothing in the device, or on the phone, for an attacker to steal that would open your door.
What it needs
The backup needs a nearby phone that has internet, to bridge the controller. If the controller is offline and no Wylmi phone is around to relay it, opening simply waits until a connection returns.