We use Bluetooth because it is convenient and secure and most devices support it natively. Encrypted connection is established between mac, iPhone or iPad. Bluetooth also has the ability to wake devices, enabling silent sync to devices in standby-mode. Convenient!
Why not wifi?
The reason we use bluetooth instead of wifi, is because public wifi, libraries, schools, work etc. doesn’t support bonjour, because they disable multicast: bonjour fails on public wifi as such bluetooth is a better choice for local devices to syncronize data.
We call it the tether. It’s a proprietary p2p technology we have built on top of bluetooth. Enabling peer 2 peer connectivity between many devices. Keeping multiple database changes in sync. Similar to how a blockchain works. Since we have to be able to syncronize offline databases. More info to be announced soon.
Essentially Passguard is a zero-trust password-manager. Data only travels between your devices locally over bluetooth. And never to any online servers. The app doesn’t even connect to the internet, and even works in flight-mode.