FolderMount - Link folders from internal SD to external to free space

Features of FolderMount:

• Root is an absolute MUST. No root, no access to app.


• Mount internal SD card folders to external SD folders.


• Move content from internal to external when a pair is added. (Dialog prompt)


• Support for Android 2.3 - 4.4.


• Holo themed throughout and an intuitive GUI design.


• It will check SDCARD mount status and remount if necessary.

Why would you need this app?

Today some apps store big files over the internal SD card (e.g. Games, Podcasts, Offline RSS feeds, Pictures, Offline navigation software). Typically users have a small internal sd card size (~16GB) while the external SD is a lot bigger (~32-64GB). Most of these apps don't have an option to use the external SD card to store data so they starve your internal SD card memory. I'm bringing this solution to fix this issue. In my case, I use this app to mount offline navigation software and some GameLoft games (NFS anyone?).

Doesn't this do the same thing as previous apps?

There are a few apps that already do this. However, my app differs in that:

a) Some of the existing apps aren't maintained anymore. FolderMount will be maintained by me as we go forward.
b) While most of the previous apps work properly in most cases, I found them not very intuitive to setup initially and were lacking some necessary "sanity checks" before linking folders. I intend to keep this app as intuitive and bug free as possible.
c) Support for Android 4.2.2! No app will currently do that for you, so here it is. (dev talk: this uses the debuggerd service trick to get it to work).

Users that buy the premium key will get:

• Unlimited folder pairs (free version has a limit of 3).


• Ability to mount any subfolder in the internal sdcard. (free version has restrictions on Android obb and data folders)


• Get to see the folder sizes in root explorer


• Support the developer and make him very happy 

Mini how to

1. Click add to add a folder pair


2. Select a source directory that you want to move files from. This should be somewhere in your internal sdcard. Usually located at /mnt/sdcard


3. Select a destination directory that you want to move files to. This should be some folder in your external sdcard or OTG drive.


4. FolderMount will offer to move the files to the destination. Click yes.


5. After the moving process is done, click on the pin. If the pin is green, you're all set.
   Note: The files will appear in both the source and destination after pinning them. This is normal as the files that you see in your internal sdcard are actually located on your external sdcard. This is how FolderMount "tricks" apps that don't have the ability to save explicitly to the external sdcard.

Screenshots:

      

Video tutorial(s):

1. by KiaTheKing

Translations:

Want to have FolderMount in your language? Help us by joining our crowdin project. More information here:http://www.devasque.com/foldermount/translations.html

Bug reports:

FolderMount version 2.2 and up support an integrated bug report and submission capability. Use the feature in the Settings menu to submit bug reports.

Changelog:

v2.6.3 (2/10/2014)

• Updated Spanish, Slovak, Hungarian, Chinese (Traditional), Latvian (new) and Russian. We have two new translators: xlen and dphilvl. Thank you volunteers!


• Fix a very rare issue where both sd cards might disappear in some Sammy TW KK ROMs. (Note 3 and S4)


• Substantial speed and on-boot improvements for users on Android 4.2 or higher running SuperSU 1.93 or higher. If you have just upgraded to SuperSU 1.93, run it once, let it update the su binary, then reboot.

source XDA