Cache Firebase on Device

Hello all,
in the forum I have always found some info, but not really understood how I can implement this.

I have a database in Firebase that I can also access without problems with the connector and Google Firebase/Cloud Firestore. I have not used Rest API.

Now the database is quite large, so that on the device the loading process takes quite a long time and I do not want to retrieve each time the new.

Is there a workaround or tutorial that shows me the individual steps how I save the database after installing the app on the device and how I can best manage to update the database if the database was changed in firebase.