Different storage lifecycles
- Some data/configuration should be modifiable at development time, and persisted back to the source tree (by developers only) but once "shipped" that cannot be changed. So the app running in "developer" mode will allow and observe changes to the source tree. This is application data.
- Some data/configuration is specific to a particular device/user and should be remembered between runs. This is user data.
- Some data can be forgotten when the application is stopped, this is transient data.
- Some data is coming from a web service or another application, this is external data (although for the application we are getting data from it may be one of the above).
It's helpful to keep this in mind when designing the library for storage. It should be relatively easy to manage the three stages of data.