AOSP ROM Android 6.0 Marshmallow custom ROM is now available for the Samsung Galaxy S3 users. The XDA developer brainlev has published the first public and working AOSP ROM based on the Android 6.0 Marshmallow. This is particularly for model no. GT-i9300, and won’t work on other Galaxy S3 sets. If you are the owner of Galaxy S3 in US from T-Mobile, AT&T, Verizon, Sprint, US Cellular, etc. then do NOT try this AOSP ROM on your Galaxy S3.
Your warranty is void if you follow the given instruction in this guide. We the Howtorootmobile.com team or the developers are not responsible for bricked devices, dead SD cards. Read all the instruction very carefully and Perform everything at your own risk.
CHECK PHONE MODEL
This guide is only for the Galaxy S3 android smartphone. Don’t try this method on any of other Android devices, It may hard brick your device. So, first confirm your phone model number in your android phone settings. To do this Go the Settings page of your device and check out the “About Device” option.
PRE-REQUISITES AND REQUIREMENTS
Before following the below Mention guide, It’s always recommended to follow our pre-requisites and requirement to stay safe.
1. BACKUP YOUR ANDROID DATA
Do take the Full Backup of your Android Apps, SMS, Contacts, Call Logs, Bookmarks. This one is one of the most important step that you have to follow, as we don’t want anyone losing their personal data or apps. For help on Backup and Restore check out the below mention guides.
2. INSTALL GALAXY DRIVERS
First you need to Setup ADB and Fastboot Drivers on windows PC. This will help you to sendbasic linux commands, and a variety Android specific commands from PC to connected Android devices.
Now you need to install the USB drivers to connect your device with the computer to follow this guide. Without these USB drivers you can’t connect your device to the PC, first download and install these drivers on your system.
3. ENABLE USB DEBUGGING MODE
Now you need to enable USB debugging mode. Without enabling USB debugging mode on your device you can’t start the root, Custom ROM or Unlock process.
4. CHARGE YOUR ANDROID
If your device switched off during this process, it could damage or brick the device. Make sure that your Android battery is full charge or near about 50-70% battery level.
After following the above mention steps follow the below mention guide one by one to proceed with the tutorial. All the above mention steps are very important, so do follow all the steps and do exactly what is told.
Install Android 6.0 on Galaxy S3
Step 1. To get started, you need a rooted Galaxy S3 with Latest TWRP recovery.
Step 2. Now download the ROM, Gapps file from the below mention links.
Step 3. Once both the files are downloaded. Move all the zip files on your Galaxy S3 phone internal memory.
Step 4. Boot your phone in TWRP recovery mode.
Step 5. From TWRP tap on the wipe and select Factory Reset. You can also choose Advance Wipe but make sure to tick the boxes next to System, Data, Cache and Dalvik Cache. Swipe to commence.
Step 6. After this go back to the Main menu and Tap on Install option, Locate the ROM and flash it.
Step 7. Now flash the GApps zip file on your phone.
Step 8. Reboot once done and enjoy Android Marshmallow on your Samsung Galaxy S3.