Only Google addresses an owner has added can get in.
Off, and you are signed out when you close this. On, and this device stays signed in for 30 days, so anyone who can unlock it can give players things — the right trade on your own phone, the wrong one on a shared machine.
The code is in the player's Settings and in the support e-mail. Typed any way round — spaces, no prefix, O for 0 — it still finds them. An e-mail address works too, for players who signed in: the address is matched as a hash, because this service does not keep anyone's address.
Both ask you to type the last four of a code first. The runbook sends you here for a deletion request and for two records that are one person.
Everything here is a row, not code. Adding a game is this form; what a game can give is the list inside it.
Someone signed in on a second device with an account another record already holds. Nothing was moved: a sign-in arrives as a plain string and does not prove whose it is, so joining the two is your call.
The service backs itself up every day, on the server, and keeps 14. Fly also snapshots the whole volume daily and keeps 5, but that is a copy of the disk taken mid-write, so it is a last resort. Neither leaves Fly: download a copy now and then and keep it somewhere else.
Each person signs in with their own Google account, and everything they do is recorded under their address on the Activity tab. Removing someone signs them out everywhere at once. The emergency key is not on this list: it is in the Fly secret, and it still works if everyone here is locked out.