HTC One A9 user will now taste the flavor of first ever Android Marshmallow update for their device and this is possible through a Custom ROM with stock root access on it. This is unofficial firmware but has all the features of the Stock Android 6.0 Marshmallow. As there is  no news by the manufacturer or Google for the release of the Stock Android Marshmallow for the handset, the users can give a try for this CustomROM based Android 6.0 Marshmallow.HTC One A9

As the ROM is in it’s developing stage you may face some bugs, but overall it will be good experience to have Android 6.0 Marshmallow with root access on your HTC One A9.

So those who want to try this newly releases Android Marshmallow update can follow the simple steps mentioned below.

Preparing your Phone:

  • Instructions limited for Sprint HTC One A9 only.
  • Phone should be rooted and its boot loader must be unlocked.
  • It should have a custom recovery tool like CWM or TWRP installed on it.
  • It’s battery should be fully charged to avoid problems during the process.
  • Phone data and current ROM (Nandroid back up) must be backed-up to retrieve it in future.
  • Phone’s USB drivers must be installed on the computer.
  • USB debugging mode should be enabled on the Phone (Settings > Developer options > USB debugging).USB Debugging

Installing Android 6.0 Marshmallow stock rooted Custom ROM:

Steps to be followed for successful installation of stock rooted Base ROM Custom ROM.

  1. Download the latest Android 6.0 Marshmallow based stock rooted base ROM for HTC One A9 from here.
  2. Download the Google App’s for HTC One A9 if not available along with ROM, from here.
  3. Connect the device to computer through the USB cable and transfer the downloaded files to phone’s internal storage.
  4. Switch off the device and reboot into Recovery mode by pressing and holding Volume down button and power button.
  5. Your device will enter into boot-loader mode and select recovery mode by scrolling down in boot loader mode and press power button.
  6. After entering into recovery mode, first perform a full data backup by selecting Backup and Restore option in the menu.factory reset
  7. Now perform a full data wipe by choosing Wipe data/Factory reset option from the menu.
  8. Similarly perform Wipe cache partition and Dalvik cache wipe (Advanced option) one after another by selecting respective options.How to reboot from recovery mode
  9. Now return to main recovery menu and select Install Zip from sdcard from the menu.
  10. Choose the file from the internal storage and flash it.
  11. Repeat the step 9 for selecting Google App’s file and flash it.
  12. After flashing both the files return to recovery menu and select Reboot system now option.

Note: Use volume keys to navigate in recovery menu and power button to select an option (Images shown are from CWM recovery)

Your phone will now boot and it will be operating on Android 6.0 Marshmallow, to check the status go to Settings > About Phone > Android Version.