Although we are working on caching the responses of REST Interface Assets requests, this will still need a first connection to retrieve the data.
In your case, a first solution could be to store your data in Excel files. These are local & persistent data that can be packaged within the experience. Once run on the device/kiosk, all the content can be local.
A more advanced solution would indeed be to create your own Interface Asset to retrieve the data using your API then store it with the solution of your choice.
- on Windows, a .NET IA can let you access any kind of local database.
IntuiFace currently doesn’t provide a way to access sqlite data bases on tablets / kiosks.