Amethyst by @Vitor Pamplona is a great nostr client. But what it does not give you (or I just fail to find it) is the right to rename your contact. If someone in the DM has no profile at all, he will forever be an npub***, even if I'd like to see him as "myserver monitoring script". In the beginning of Nostr, AFAIR, there was an idea of users giving "pet names" to other users, with a way to represent things like "@fiatjaf believes that this profile is @akovalenko". Would be great by starting with one-level contact renaming, at least.