Now all of my mobile phone is routed through orbot, says 'full device VPN', and it doesn't receive or send data. I have to pick a random app to route through orbot on the main screen to not have the full device routed. Still, Amethyst with only local citrine's onion service outbox doesn't find any notes. Doesn't work for me

Looks like Tor found a killer app on #nostr ! ..

Outboxes don't find notes, they hold your notes so other people can find them. In orbot you can enable per user more. That will give you a Tor proxy without the full device VPN 🤙

So if my only outbox is my own onion service, only someone explicitly listening to it will be able to see my notes? If man people do this, I have to add a relay for each npub?

I wouldn't set it as my only outbox, I also use others. This is more of a l last ditch effort to make sure your notes can get out. Outbox protocol works by clients knowing where your outbox is located, this information is part of your profile. They don't need to be configured, a client will connect automatically to the relay to retrieve your notes. This is all a work in progress as well, so ymmv It also works for DM