how to sync a journal between devices

sync is off until you turn it on. when you do, your writing is sealed on the device it was written on, and the relay keeps what it cannot read. two devices are free, and you can run the relay yourself.

turn it on

open settings and start sync. the app generates a recovery phrase of twenty-four words. write it down somewhere that is not the device you are holding: that phrase is the account, and it is what rebuilds your keys on a new install. losing it loses the writing that only exists sealed on the relay, because nobody here can unseal it for you.

add the second device

install the app on the other machine and enter the same recovery phrase. the keys are derived from the phrase on that device, so the second machine does not need the first one switched on to join. from then on, a page you write on your phone is on your desk when you sit down, and the same the other way.

this is the part people mean by a journal app that syncs between devices: not a copy in somebody's cloud, but the same writing on the machines you use, with the middle unable to read it.

what the relay holds

content, titles and file names are sealed before they leave the device. what the relay does see is the shape of the traffic: how big the sealed blobs are, when they arrive, and which ones belong together. that is written down rather than waved away in the threat model, and the primitives are named in how sync is encrypted.

run the relay yourself

the relay is agpl-3.0-or-later, and it is a small service to host. if you would rather not use ours, the deploy guide walks through it, and nothing in the app changes: the same phrase, the same sealed pages, a different address.

more than two devices

two devices sync for free. a third and beyond is the one paid thing here, and it pays for the relay we run; a relay you run yourself has no such limit. the app itself stays free either way: what that costs.