Ah yes, Android storage. When launched the concept seemed to be that "internal storage" was the emmc, while "external storage" was the SD card (or equivalent).

Ah yes, Android storage. When launched the concept seemed to be that "internal storage" was the emmc, while "external storage" was the SD card (or equivalent). Then came the idea of faking an SD card on the emmc via partions, but SD cards were still an option (but no standardized mount point any longer because it was used for the faux SD partition). Then came 3.1, and Google changed up the permissions such that "external storage" permissions only applied to the faux SD parition, and new "media storage" permissions were needed for actual SD cards (but still no official mount point, and the write to SD permission was reserved for system, aka bundled, apps). This state persisted until 4.4/5.0 where Google introduced the Storage Access Framework. Effectively the new name for accessing SD cards via the mediaserver APIs. The mediaserver being the daemon that indexes all user storage areas and makes the results available to music and video players (and also handles USB storage connections via the MTP protocol). Supposedly all this was done so people would no longer be surprised that they could not access the SD card from both inside the phone and the PC when connected via USB (because Linux requires that a partition is unmounted locally when exposed over the UMS protocol). But that would not require that more stringent media storage permissions. Frankly those permissions reeks of being introduced because of MAFIAA arm twisting. Not only is the naming interesting, but Google made a grand unveiling of their music and movie sections of the then Android Marketplace (now Google Play Store) soon after.