HTC rolled out the Android 4.2.2 software update for its flagship smartphone HTC One earlier last month. Now it appears the latest Jelly Bean software, Android 4.3, is on its way for the handset.

The Android 4.3 update featuring Sense v5 with base firmware 3.09.401.1 has leaked for the international version of HTC One M7. The leaked firmware integrates New Hboot 1.55 and Radio 4A.19.3263.13_10.38j.1157.04L. This leak has been shared by recognised XDA contributor LlabTooFeR who promises to release the original 3.09.401.1 dump on 28 August.

There is good news for HTC One users who wish to experience the leaked Android 4.3 firmware. The developer has released a custom build dubbed as Maximus HD 12.1.0 featuring Android 4.3 (3.09.401.1). The ROM carries several customised features and tweaks.

Android 4.3
Maximus HD ROM featuring leaked Android 4.3 is available for the HTC One.

Maximus HD 12.1.0 features

Based on HTC One 3.09.401.1

Android 4.3 Jelly Bean

Sense 5.0

Amazing battery life

Fast and Stable

Tweaked for best performance

OTA updates

APM

Native HTC EQS

Auto-Kernel Flash

Deodexed

Zippalinged

Rooted

Options to remove unneeded apps

Options to install additional mods

Support of init.d

Changelog

MaximusHD 12.1.0

Fixed SU

Fixed System RW issue

Replaced koush SU with Chainfire SU

New Base 3.09.401.1

Android 4.3

Added Bluetooth 4.0 LE support

Added OpenGL ES 3.0 support

Added Google Wi-Fi Scanning feature

Added Google Games

Added ability to wipe device remotely

Added Ability to use HTC TV in countries without TV programmes available

Updated Kernel

Updated AppDrawer

Updated System Fonts

Updated OEM Apps

Supported devices

M7_U

M7_UL

M7 AT&T

M7 T-Mobile USA

Android 4.3
Android 4.3 pre-released firmware leaked for the HTC One.

Those who wish to install Android 4.3 (3.09.401.1) on their devices using Maximus HD 12.1.0 ROM, may follow our step-by-step guide. To install the ROM, the HTC One should be unlocked or have s-off (Security Off).

IBTimes UK reminds its readers that it will not be held responsible for any damage to the device. Users are also advised to ensure that their devices meet following requirements.

Pre-requisites

1) Install USB Drivers for HTC One to transfer files between the Android device and computer.

2) Enable USB Debugging Mode on phone to connect it with computer and use Android SDK with it. [Press Menu>> Settings>> Applications. From there navigate and click on Development option and check USB Debugging Mode.]

3) As the tutorial is likely to wipe out all data of the phone, create a backup. If the device is having any custom recoveries such as ClockworkMod/TWRP already installed then backup data using the recovery.

4) The HTC One should have above 80% battery charge.

5) The phone should be rooted and have ClockworkMod (CWM) recovery installed. Click here for our guide to unlock, root and install CWM/TWRP recovery on HTC One.

6) The maximus HD 12.1.0 work only on HTC One. Installing this on any incorrect variant might brick the device.

7) After flashing the ROM if the device gets stuck on Booting animation or experiences boot loop, then perform wipe cache partition and wipe dalvik cache five more times and then reboot the device.

8) Users are advised to give five to 10 minutes to the ROM once the device boots up for the first time to settle everything for a better user experience.

Steps to install Android 4.3 (3.09.401.1) on HTC One with Maximus HD (12.1.0)

Step-1: Download Android 4.3 Maximus HD custom ROM for HTC One to computer

Download link [Alternative link]

Step-2: Connect the HTC One to the computer using USB cable. Transfer the downloaded zip to the internal SD card of the phone

Step-3: Unplug the USB cable from the phone and turn it off

Step-4: Boot the HTC One into recovery mode. Press and hold Volume Down and Power buttons together until the screen flashes. Now from the HBOOT menu navigate to Recovery option using Volume Down button and select it with the Power button

Note: In recovery mode use the Volume buttons to scroll between options and Power button to select the desired option.

Step-5: In recovery mode, it is important to perform a Nandroid backup of the existing ROM which can be restored later if the new ROM does not work or in case users wish to go back to the previous firmware. To perform a Nandroid backup, select Backup and Restore then on the next screen select Backup again. Go back to the main recovery menu once the backup process is done

Step-6: Perform data wiping task to eliminate clash between the new ROM and the previous ROM. To do so, select wipe data/factory reset then select Yes on the next screen to confirm the action. Wait for few minutes until data wiping is done then return to the CWM recovery menu. Select wipe cache partition and after wiping cache partition is completed, select Wipe Dalvik Cache under advance option to perform Dalvik cache wiping. Once the action is completed, go back to the recovery menu

Step-7: Select install zip from sdcard then select choose zip from sdcard. Now navigate to Maximus HD ROM zip which was earlier copied to the SD card of the phone. Select it using Power button and confirm installation on the next screen. The ROM installation should begin now

Step-8: When the installation process is completed, return to the main recovery menu and reboot the phone by selecting reboot system now. The phone will now boot up into customised Maximus HD ROM. The first boot will take about five minutes

As the HTC One boots up, it should be updated with Maximus HD 12.1.0 custom build featuring Android 4.3 3.09.401.1 leak firmware. To verify the new software version running on the phone head over to Settings>> About phone.

Note: To go back to the previous ROM, boot the phone into recovery mode, select Backup and Restore then restore the ROM by selecting it from the list.

[Source: XDA]