The goal of this NIP is to enable [remoteStorage](https://remotestorage.io/)-like capabilities for custom applications that do not care about interoperability.
Even though interoperability is great, some apps do not want or do not need interoperability, and it wouldn't make sense for them. Yet Nostr can still serve as a generalized data storage for these apps in a "bring your own database" way, for example: a user would open an app and somehow input their preferred relay for storage, which would then enable these apps to store application-specific data there.
This NIP specifies the use of event kind `30078` (parameterized replaceable event) with a `d` tag containing some reference to the app name and context -- or any other arbitrary string. `content` and other `tags` can be anything or in any format.
