How to Enable Multi-Window Option on Android Marshmallow

Google released Android Marshmallow with some new features and improved user interface, but there is a new feature wasn’t announced in the keynote it’s multi-window mode.
Finally multi-window feature will be on stock Android build and it should arrive to all devices which will update to Android Marshmallow.
To get multi-window mode working you need to modify the build.prop system file to show up the feature settings in developer options.

Steps:

1. Download and install “ES File Explorer” App on your rooted Nexus phone, root your device on Android Marshmallow.
2. Open “ES File Explorer” and press on the top left icon.
3. Press Tools then choose Root Explorer.
   
4. Hit Mount R/W, change Path “/” and “/system” from RO to RW then press OK.
   
5. Once you press OK SuperSU will ask for root permission hit GRANT.
6. Press the top left icon, hit Local then choose / Device.
   
7. Go to: /system folder, scroll down to “build.prop” file, take a backup of that file before modifying it.
8. Now open “build.prop” file as text in “ES Note Editor”.
   
9. Press on the top right icon (3 dot) and choose Edit.
10. Find the “ro.build.type=“ line.
11. Change it from:
    ro.build.type=user
    to:
    ro.build.type=userdebug
    
12. Hit the back button then press Yes to save the file.
13. Reboot your device to apply the changes.
14. Go to the developer options, enable developer options by going to: Settings > About phone, tap Build number 6 times until you see “You are now a developer” hit back button to go to the main screen of settings, now you will see a new option “Developer Options” open it.
    
15. Scroll down to “Drawing” category.
16. You will find multi-window mode enable it.
    

How to use multi-window feature?

1. Press multi tasking button a new button will appear on the top of every opened App.
2. Tap the icon and select the layout (window up, windows down, full screen).
   

Voila, now you have multi-window working on your phone

Samples: Landscape mode
Samples: portrait mode

Please note that:
– This feature is working with All Apps stock and third party Apps but you may notice some bugs as its not officially enabled by Google.
– If you are going to apply multi-window feature to your device please do it at your own risk.

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