Android 4.3 on Galaxy S4 Google Edition breaks SD card writing for apps, here's a fix

The reason for this is a bit technical and is related to how Unix handles write permissions. Basically, there's a special group that apps must be a part of to be able to write to the external storage, but most apps are yet to be updated to adapt to this change. ES File Explorer is one app that has the correct permissions, and while an official fix might not come any time soon, a temporary fix is available to take care of the problem.

You'll need to be rooted in order to fix the issue, after which you can follow the steps below to let apps write to the SD card again:

1. 1. Use an app like Root Explorer, Solid Explorer, Root Browser, or any other root explorer app to access system files. 
2. 2. Go into the system/etc/permissions folder, then edit the platform.xml file on the phone itself or copy it to the PC and edit it there.
3. 3. Look for the line that says name=”android.permission.WRITE_EXTERNAL_STORAGE” >. Under this should be the line <group gid=”sdcard_rw” />.
4. 4. Now, under “<group gid=”sdcard_rw” />“, add <group gid=”media_rw” />, then save the file. The screenshot on the right shows how the final text should look like. 
5. 5. If you edited the file on the computer, copy it back to the phone and replace the original file, but not before backing up the original file somewhere.
6. 6. Now, reboot your phone to make the changes take effect.

Your phone should now allow apps to write data to the external storage. It's not the solution we would like, but unless Samsung and Google push out an update to fix it themselves or apps are updated accordingly, it's a solution you'll have to live with (tough luck if you're not rooted).

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