Android Storage Locations

Question

Can someone explain in detail about the various storage locations in Android,

1. /sdcard/ (along with /root/ directory and other system-level directory)
2. /storage/emulated/0/
3. /storage/emulated/legacy/
4. /storage/sdcard0/

Really confused with these? And are there any methods to access them programatically whenever needed?

Answer 1

I can't speak for storage paths on all phones. But I can explain you clearly with respect to my phone; Coolpad Note 3 - running on Android 5.1. Because, the storage locations or paths may vary on other mobile phones depending on your vendor/manufacturer and different versions of Android OS.

Generally, /someDirectory or /root/someDirectory or >root>someDirectory are same. Which among them is picked to display; depends on your file manager.

On my phone:

/root/sdcard is storage path to phone's internal memory(16 GB in my case).

Both /storage/emulated/0/ and /storage/sdcard0/ are symlinks to /root/sdcard. It means, these two paths are also storage paths of my phone's internal memory.

/storage/sdcard1/ is storage path of my micro SD card.

On ANY phone:

Before Android 4.2, only one user could user your phone. There was no concept of two or more users creating separate profiles and logging into the same phone.

As a result, there were no such paths like /storage/emulated/someDirectory

The emulated directories came up after the introduction of multiuser API in Android 4.2.

Source: source 1 and source 2

So from then,

/storage/emulated/legacy/ points to External Storage(Android terminology) of the currently working user. It would be a symlink.

/storage/emulated/anyNumber/ points to External Storage(Android terminology) of a specific user.

On my phone: I have two users.

internal memory location for user1 (Ramesh) is: /storage/emulated/0/

internal memory location for user2 (Kishore) is: /storage/emulated/10/

So /storage/emulated/legacy/ would point to /storage/emulated/0/ if user1(Ramesh) logs in & uses the phone. In this case, /storage/emulated/legacy/ would be a symlink to /storage/emulated/0/

And /storage/emulated/legacy/ would point to /storage/emulated/10/ if user2(Kishore) logs in & uses the phone. In this case, /storage/emulated/legacy/ would be a symlink to /storage/emulated/10/

If you want to know more about storage paths, please go through this answer on android.stackexchange.com

I specifically mentioned External Storage(Android terminology) above. Because, the Internal and External Storage terminology according to Google/official Android documentation is quite different to that of normal Android OS user.