Michael Bechtold did an incredible job producing these maps. For each zoom level he used different an multiple sources ensuring best usability by providing a reasonable filesize. Best is that he aggreed to share these maps for free with our community on OpenAndroMaps.
These maps are pixelmaps in sqlite data format plus a special version for Oruxmaps. Pixelmaps are the best choice for general maps cause they load much faster at low zoom levels compared to vectormaps while vectomaps are providing much more detail at high zoom levels for a fraction of the filesize.
The pure sqlite-maps (for Locus and all APPs capable to handle sqlite) are not compressed so you don’t need additional space and time for decompressing while quick-installation on your device.