Foil Auth

And another round here: Chum is your friend if you want an armv7hl build linked against openssl1.1. There's nothing wrong with linking openssl1.0 or anything else statically if it's not part of the OS anymore.

If you copy the key ~/.local/share/foil/foil.key and encrypted files from ~/Documents/FoilAuth to another phone, the secrets should get loaded. Note, however, that if you overwrite ~/.local/share/foil/foil.key with a different one, you lose access to the secrets encrypted with the old key. Be careful.
Another (and safer) way to transfer OTP secrets between devices is a QR code - show it on one device and then read from the other, that works between devices with different keys. There is even a bulk sharing function on the Select page. No bulk import though (yet).

I'll tell you more :) If you build foilmsg tool then you can decrypt your auth tokens on your computer, you don't need a phone for that. Suppose you have pulled a file named 5E6FD647B7683FAC from your ~Documents/FoilAuth directory. And foil.key file too, of course. Then you can do something like this:

$ foilmsg -d -s foil.key -P xxxxxxxx -f 515B8BF49C1DF7E5 -o secret -v
[foilmsg] Private key fingerprint: 53:ae:7e:54:c2:d2:43:88:2a:98:a0:24:4a:90:66:1f
[foilmsg] Found 3 header(s)
[foilmsg]   OTP-Label: test2
[foilmsg]   OTP-Favorite: 1
[foilmsg]   OTP-Digits: 6

where foil.key is your foil private key file, xxxxxxxx is your foil password. Your secret token is written to the file named secret in the binary form, i.e. as a sequence of raw bytes - in order to get the token string the way you see it in FoilAuth app, you would have to run your secret bytes through a Base32 encoder.