Determine if app should be usable offline or require a network connection

[MajorMapInitiative]

This is done when:

• It is decided whether to store large files on device or use an API.

[p8gonzal]

I would suggest to require a network connection. There are probably few instances in which no network connection is available. By contrast, storing large files on a mobile app encourages users to delete them if they are short on memory. It would also limit our ability to keep the app up to date with events and updated classes.