Just tried it. Has a few small issue that'll get fixed, but after I asked the devs (I think) and read their nip, it's real good! This was going to be in My Nostr Wishlist #2 post, but now it has been fulfilled =3 (what was fulfilled? Npubs are hidden / even if someone gets ahold of your npub, they wouldn't know who you're DMing with. They just strings of text and doesn't lead back to your npub unless you mention it.

nostr:note1ankuf7ju93rwk3y0qn9kasc57hzw3f86saklnxu89xxg9wggps5s68n8tq