Extend internal memory of any Android device (Root Needed)

Low internal memory is a very common problem between low end android devices. Today most of android devices have both more than enough processing power and RAM size. But the internal memory size is relatively low. Due to low internal memory, we can't install many apps and most of the times sync stops working.

Two most popular solutions to low internal memory problem.

1. Link2SD
• Drawback - Slow down the device
2. vold.fstab method
• Risk of bricking the phone. Need the appropriate vold.fstab for the device.

I'm going to tell you a different method. In this method the SD card is joined to the end of the internal memory. If the internal memory is not enough, then the SD card will be used instead of the internal memory. 

I installed NFS Most Wanted and NFS No Limits on a Xpeia E3 Dual after extending the internal memory using this methods. (Xperia E3 Dual has a internal memory of 1.7 GB)

Why you should use this method

1. No limitations. This is suitable for any android device. (Root needed)
2. No risk of bricking the phone. 
3. Can download large games like NFS and GTA from goole play.
4. You can remove the trick at any time you want easily. 

Requirements

1. Rooted Android device. (Root guide for Xperia E3 dual)
2. A SD card with good read write speed and a desired capacity. (Class 10 SD card is highly recommended)
3. Download these.
• File Set
• Install ROM Toolbox Lite from google play. 
• OBB on SD Xposed Module

Method

1. Extract downloaded File Set.zip and copy files to SD card of the phone. 
2. Move debuggered.mnt file to system/bin folder of the android device. (Use Root Browser of the ROM Toolbox Lite to do this). Set the permission as other files in the system/bin folder. (Permission can be set by long touching the file.)
   
3. Open the scripter of the ROM Toolbox. Press plus button on the action bar and import the mount.sh file from the folder copied to the SD card.
4. Click on imported mount.sh file and click "Run Script". Script will be run and memory will be extended. (If you check in the file browser of the phone, it will display the extended memory size for the internal memory)
5. Now click again the mount.sh file and click "Set at boot". This will set the file to be run at every startup. 
6. Now install the OBB on SD Xposed module which was downloaded before.

Yeah. Now you are done.

Optional step (Carefully read and only do this if necessary)

Some phones have SD card write permission problems, especially devices with Kitkat OS. To check this do the following simple steps.

1. Go to broswer and and check whether you can download files and images.
2. Open the facebook app and try to save an image.
3. Open whatsapp and try to download an image or a video. 

If any error occur while performing above steps, then follow the following steps. If no error occurred and everything works fine, then just ignore following steps and you are done.

1. Download and install Xposed Installer.
2. Open the app and then activate and reboot.
3. Go to Modules in Xposed Installer and install Kitkat SD card full access and Obb on SD. If directly installing from the Xposed installer didn't work try above links and download and install externally. 
4. Enable by marking the check box for above two modules.
5. Restart the device.

Yeah. Now you have extended your phone's internal memory successfully. Enjoy playing a big game from google play. 

If you have any questions feel free to put a comment. And also please be king enough to leave a feedback :)

Reference - XDA Forum