Update: both points are addressed now. 0.17: a personal watcher runs on your own machine, so the view key never leaves you. 0.18: tip amounts are hidden by default, intent and receipt no longer carry the amount. Guide: 

monero

monostr: a Nostr client with Monero tips instead of zaps (public beta, Android)

schmidt

Update: both points are addressed now. 0.17: a personal watcher runs on your own machine, so the view key never leaves you. 0.18: tip amounts are hidden by default, intent and receipt no longer carry the amount. Guide: https://github.com/schmidt1024/monostr/blob/main/watcher/SELFHOST.md