Shipping and updating app with deeply nested JSON data


I’m in the middle of creating an app. The app is a configurator where the user picks out of a list of parts with each carrying dependencies. Dependencies will work as filter for the following lists of selection. The JSON file is probably around 5-10 MB in size. Parts will be added and removed over time so i need syncing. Goal is to have daily updates at some point.
I looked into Firebase but it doesn’t seem to work well for larger, nested data. Couchbase with Sync Gateway is another solution i found, but wonder if that’s not overkill. Also it appears to require large server.
The app should always be working as good as possible when offline. It’s a pure reading app from the mobile point of view, data will be pushed from an admin backend.
The market is quite convoluted and i would appreciate some pointers in the right direction.