As I showed in a previous post SharePoint is different Interfaces you can use to access as a data source.
So I we know it can expose it’s List data using the REST or oData protocol.
Open PowerBI and go to GET DATA menu.
Choose OData Feed to connect to your SharePoint data source
Once logged you can choose from your lists
And play around to make your data visible using all the features from PowerBI
Once Finished you can publish your result
Once published you can reach out on the mobile apps.