GM!
I remember people #asknostr for e2e encrypted collaborative note-taking apps that work offline. Here a simple list app which works offline and syncs via nostr using a shared nsec for encryption
https://testr-072e4a.gitlab.io/?testr#nsec1flyyr3v6w393epu8jfqzrw92hyys8m0c09s3v8qppst42glv8nxq0ezzpx
The data replication sync engine is a reusable library to enable resillient local first #grownostr apps.
#farmster