Rooted Galaxy Grand Duos I9082/I9082Lusers can update their phone to Android 6.0 Marshmallow unofficially. Thanks to the XDA member pawitp for porting the Android 6.0 Marshmallow for Grand Duos. The AOSP based ROM will bring pure Marshmallow experience on your phone.

The ROM status is Alpha, which means, it is not a fully functional ROM and not ready to be used as a daily driver yet. A number of things do not work, so use them at your own risk. What does works (as of October 13): Wi-Fi/Bluetooth Sensors (Accelerometer, Compass, Light, Proximity, etc.) Camera Video (playback & recording) Audio (playback & recording) GPS Everything else not listed under “known issues” What does not work (As of October 13) RIL (Calls, SMS, Mobile Data) does not work Dual SIM does not work FM Radio does not work SELinux is in permissive mode Runtime storage permission does not work properly Sometimes wake up causes music stutter [We assume that the developer will fix all the issues soon. Tech savvy users can tryout the ROM now at their own risk] Installation Instruction : Note: Before installing this ROM, download [HERE] and install the CWM recovery with SELinux support. Older CWM recovery will result in a “status 7” error. Does not work on 4.1 stock ROM’s bootloader, please upgrade to 4.2 before flashing.

  1. Download the Android 6.0 Marshmallow ROM zip file [HERE] and copy the zip file to root of your SD card (not in any folder)
  2. Now, boot your Grand Duos into custom recovery mode. To do so, switch Off your device and press Volume (+), Menu, Power buttons together.
  3. From recovery, do a full wipe (cache partition, data wipe/factory reset, dalvic cache)
  4. Now, choose install ZIP from SD card and select the ROM zip file (use Vol buttons for navigation) and flash it.
  5. If you want, flash Google Apps as well (have a search on Google to find Marshmallow compatible Gapps)
  6. Once again, do a full wipe (Data wipe/ Factory reset, cache partition and dalvic cache)
  7. Now, go to the main menu and select ‘reboot system now’. That is it. Your Samsung Galaxy Grand Duos will boot into Android 6.0 Marshmallow OS version. Important Note: Keep in mind that, currently above mentioned ROM is experimental and contain several bugs. It may brick your device, so use at your own risk! (Source – XDA)