| BaseExtension | Abstract base GeoPackage extension | 
| CrsWktExtension | OGC Well known text representation of Coordinate Reference Systems extension | 
| ExtensionManagement | Extension Management for deleting and copying extensions | 
| ExtensionManager | GeoPackage Extension Manager for deleting and copying extensions | 
| Extensions | Indicates that a particular extension applies to a GeoPackage, a table in a
 GeoPackage or a column of a table in a GeoPackage. | 
| ExtensionsDao | Extensions Data Access Object | 
| GeometryExtensions | Geometry Extensions utility methods and constants | 
| WebPExtension | WebP extension | 
| ZoomOtherExtension | Zoom Other Intervals extension |