Yes, stamps can be millisats if the mint supports that. We've built that option, dunno if 0xChat would be able to handle it. I also don't know of any mint that runs on msats though.
I think I became a keychat maxi in 2 hours of using the app lol
3 questions
Can stamps be sub 1 Satoshi level (I think that is a question for nostr:nprofile1qqs9pk20ctv9srrg9vr354p03v0rrgsqkpggh2u45va77zz4mu5p6ccpzemhxue69uhk2er9dchxummnw3ezumrpdejz7qgkwaehxw309a5xjum59ehx7um5wghxcctwvshszrnhwden5te0dehhxtnvdakz7qrxnfk)?
Could a relay be setup that is based on USD mints? Like say 1ยข/message?
Do I have to onboard the person I DM on keychat to keychat before they can read my message? Or do I just tell them to add that relay? Could they still DM me?