[Galaxy S III I9305 (4G LTE + 2GB RAM) Android Deve] l3ong91:
Hi, it has been a while since I am active on XDA forum. This following method may have work for other S3/ Note variants since awhile back. But since the Android 4.1.2 has just released ( At least in my region) for Samsung Galaxy S3 LTE I9305, I have tested this and I can prove that it's working on this phone as well.

In case you don't know what is MultiView (Only available on Android 4.1.2 Updates),

Following is a relatively noob-proof tutorial to show you how you can mod almost any apps to work with multi-window without rooting your precious phone.

WHAT YOU NEED

- SAMSUNG Galaxy S3 LTE I9305 running Android 4.1.2

- Windows PC

- Latest Java JRE ( Download here )

- Latest Java SDK ( Download here )

- Apk Multi Tool ( Download here )

- General keyboard typing skills

INSTRUCTIONS

SETTING UP THE APK MULTI-TOOL

1. Make sure you update your Java JRE and JDK first before we proceed with the rest of the steps below.

2. [OPTIONAL] You can get the apk file for your desired apps via third party market or you can backup all existing apps on your mobile using App Backup & Restore and it will automatically convert all apps to .apk format.

3. Create a new folder on your desktop, named it as " Apk" or whatever file name you like, and transfer the apks from your phone to that folder.

4. Create another new folder, named it as "apk manager".

5. Unzip APK Multi Tool into the root of "apk manager" folder.

6. For the first time only, go into apk manager> APK-Multi-Tool> Run setup.bat

7. Once it's running, type "3" and let it create the sub-directories and folders for you, then just press ANY key to continue.

8. When it's back to the main screen, type"00" to quit the cmd.exe screen.

DECOMPILE THE APK

1. Copy the apk that you would like to decompile from the "apk" folder you created earlier on desktop.

2. Paste it inside apk manager>APK-Multi-Tool>place-apk-here-for-modding folder

3. Next, run the script.bat.

4. Press any key to continue, follow by a screen full of different running numbers and description.

5. Type "9" and hit Enter to decompile the apk you placed at "place-apk-here-for-modding" folder.

6. Be patient, wait for the "test..." to finish and you will see the "test..." disappear and goes back to "Please make your decision..."

7. Minimize the cmd.exe for now, and go back to the "APK-Multi-Tool" folder. DO NOT EXIT THE SCRIPT.BAT

8. Go to "projects" and you will see the decompiled apk there.

9. That means you have successfully decompiled the apk. You should be able to see folders like "res", "smali" and files like " AndroidManifest.xml" and "apktool.yml".

10. For this tutorial we only need to edit the "AndroidManifest.xml". DO NOT TOUCH THE REST UNLESS YOU KNOW WHAT YOU ARE DOING.

EDITING THE ANDROIDMANIFEST.XML

1. Open the AndroidManifest.xml with Notepad and find the following text.

<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

2. Add one more line to it so that it become

<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
[COLOR="DarkOrange"]<category android:name="android.intent.category.MULTIWINDOW_LAUNCHER" />[/COLOR]
</intent-filter>

3. Next, find the following lines near the bottom of the file.

</application>

4. Similarly, copy and paste the following codes before the line so that it appears as:

[COLOR="DarkOrange"]<uses-library required="false" name="com.sec.android.app.multiwindow" />
<meta-data android:name="com.sec.android.support.multiwindow" android:value="true" />
<meta-data android:name="com.sec.android.multiwindow.DEFAULT_SIZE_W" android:value="632.0dip" />
<meta-data android:name="com.sec.android.multiwindow.DEFAULT_SIZE_H" android:value="598.0dip" />
<meta-data android:name="com.sec.android.multiwindow.MINIMUM_SIZE_W" android:value="632.0dip" />
<meta-data android:name="com.sec.android.multiwindow.MINIMUM_SIZE_H" android:value="598.0dip" />[/COLOR]
</application>

5.Save and overwrite the existing file. Exit notepad.

COMPILE THE APK

1. Go back to script.bat on cmd.exe.

2. Type "12" for Non-system apk.

3. Wait for the compiling process until it prompts you for the input again.

4. Choose "1" as unsigned Apk and keep the original file. Wait for it to complete until a prompt appears to ask you to delete the file in the "keep" folder". DO NOT EXIT THE SCRIPT.BAT YET, MINIMIZE IT

5. Go to apk manager> APK-Multi-Tool>"keep" folder.

6. Remove AndroidManifest.xml and resources.arsc files.

7. Go back to script.bat on cmd.exe and hit Enter to let it re-compile again the apk.

8. When it's done it will revert back to the main screen of cmd.exe, type "13" to sign the apk.

9. Copy or push the apk file back to your phone to install.

IMPORTANT NOTICE

- Remember to uninstall the existing apps first before you reinstall the new signed copy of the apk.

- By doing this, your apps will not be detected by Google Play for updates and if you want the latest version, you will have to reinstall the new version and recompile the apk again in order to use this in the MultiView window.

- Although it is highly impossible, I take no responsibility in damaging/ bricking your phone should there be any problems happen to your phone.

EXTERNAL REFERENCES

In case there are any difficulties, you may look for the following guides:

Tech Freeks

XDA Forum> Verizon Galaxy Note II

Android Central Verizon Note II

Let me know if it works for you.