- Install the current version of TWRP recovery to back up all the data on the device.
- Confirm that the right USB drivers are installed on the PC for an easy unpacking of the ROM and Google Apps to the Galaxy S5’s storage.
- The next step is to download CM13 Android 6.0 Android Marshmallow custom ROM and Marshmallow Google Apps.
- Connect the S5 to the PC and copy the Android Marshmallow ROM zip file to the device’s internal memory.
- Turn off the Galaxy S5 then reboot it to TWRP Recovery by long-pressing the Power and Volume down keys together till you see a TWRP logo on the screen.
- Next a Nandroid backup should be done, by simply selecting the backup option on TWRP.
- After the backup completion, in the TWRP menu, select the wipe option then Advanced Wipe. Tap on all the options then begin the wipe process.
- Choose the install option in the main menu of TWRP. Navigate to the location of the saved ROM zip file, select it and confirm installation.
- Repeat the previous step for Google Apps installation.
The CyanogenMod developers have launched the CyanogenMod 13 ROM for the devices’ Android Marshmallow update. The ROM is still at its experimental stages thus may feature a few issues to be fixed in upcoming CM13 firmware updates. NOTE: Installation of custom ROMs and rooting devices may void the warranty on the device. This custom ROM is compatible with all Galaxy S5 models (codenames: klte, klteacg, kltedcm, klteub, klteatt, kltecan, and kltetmo) and any attempt on another variant may brick the device.
What's my model number?
There are several ways to locate your model number:
- Option 1
- On your device, go to Settings, then "About device" and scroll down to "Model number"
- Option 2
- Often times you can view the model number inside the device, by removing the battery
- Option 3
- Using Samsung's model/serial number location tool