Funny to read this, as the original scheme for Android was the OS and apps on emmc, user data on SD card. But then later some OEMs came up with partitioning th

Funny to read this, as the original scheme for Android was the OS and apps on emmc, user data on SD card. But then later some OEMs came up with partitioning the emmc and mounting one part in place of the SD card. Later still Google codified this hack by mounting a vfat union mount on top of a directory in /data as if it was the SD card. All in all Android storage is a tire fire of hacks.