GeoPackage
From Just Solve the File Format Problem
GeoPackage is an open, standards-based, platform-independent, portable, self-describing, compact format for transferring geospatial information.[1][2]
File Information
A GPKG file is an SQLite based file format.
The application ID for such a database is 1196444487 or 1196437808 for version 1. The ID expressed as strings are GPKG
or GP10
[3]