[Miscellaneous Android Development] csu333:
Well, some of you might have had the same urge to buy one of these little wonder with almost the same data sheet than a LG G2 but with a Dual SIM functionality and at a much smaller price. If you are one of these crazy people that ordered their in China just like me, you might have the same disappointment that I felt when I finally received mine: the advertised SD Card slot is just a fantasy and all Google apps have been replaced by their Baidu counterparts. If the English language is indeed present in the Operating System, none of the installed application seems to understand this language. If you just don't speak Chinese just like me, you might end up wondering why on earth you bought a smartphone destined to Chinese people.

So I decided to turn this frustration into something positive and succeeded so I'm happy to bring you my home cooked ROM for the Lenovo K910. But first of all, the usual disclaimer:

Disclaimer

Don't hold me responsible if you brick your phone. This method have been successfully tested on mine but this is no guarantee for yours. You should obviously always have a backup of your data at all time if you're willing to install this ROM (or any other).

Safety measures

Like most Android phones, the Lenovo Vibe Z have many possibilities of recovery. I would advise you to be ready to apply at least this one:

Download the QSB file of your ROM (for example, mine is K910_SS_S_2_040_0039_131101.qsb). Google will point you to a Baidu site where it is downloadable

Put it in the folder /sdcard/SDFUSE/

Shut down your phone

Hold Volume Down and Power button for a few seconds

You end up in a menu with a "SD Card Update" entry. Move down to this entry using the Volume Down button then press ENTER or power button.

Make sure your ROM is available in the list

Cancel and reboot

If your QSB file is visible in the list, you should be pretty safe. If anything goes wrong, use the same method but apply the upgrade this time. Note that this method overwrite everything included your applications, SD Card, ...

What it is

The ROM I'm offering is:

An extract from K910_SS_S_2_040_0039_131101.qsb

Applying only to your system partition (your applications and data should be safe)

Rooted

Busybox-ed

Grossly freed from most vendor applications

Replaced by Google applications

What it is NOT

This was already some work to figure out how to reach that goal so it is not:

Bug free (I have at least observed a strange display glitch for the network icons which turn standard blue instead of Lenovo's white one)

A multi-language ROM

A ROM build from scratch like MIUI, Cyanogenmod, ...

A custom recovery (though this might come in a later stage)

...

Prerequisite

You should have installed:

K910 ADB Driver (available on the CD that appear when you connect the device)

ADB

Fastboot

Just check that your USB debug mode is enabled (in the USB Access Mode menu).

In any of these prerequisite is an issue for you, I'm ready to explain you further but you should also wonder if you are ready to go further because if anything goes wrong, you won't be able to properly act.

The installation

OK, enough talking, now some action. It is pretty simple actually:

Download the ROM and un-7zip it (mirroring in progress)

Reboot your phone in bootloader mode. Therefore, open a command prompt (no matter which OS you're using) and type:

adb reboot-bootloader

Now your phone is displaying the Lenovo logo

Check that you can access the system

fastboot devices

If fastboot just return displaying nothing, you might have to run in Administrator/root mode. Under Linux, I had to use sudo.

Unlock the bootloader (this should wipe all your data if it wasn't unlocked previously):

fastboot oem unlock

Flash the system:

fastboot flash system <path-to-file>system.img

Reboot:

fastboot reboot

That's all folks ! After your phone restarts, you should be able to use Google applications (though not all of them are there, at least the Play Store is allowing you to install the others).

What's next ?

I hope to be able to free some time to achieve these next steps:

Publish the script I wrote to extract content from Lenovo QSB files

Apply the same method to the last upgrade (K910_SS_S_2_040_0078_131203 ?). If you are lucky enough to have this version please contact me to see if you can provide the QSB file.

See if I can cook a custom recovery.

This is probably my very first participation to the community so I'll accept any comments as long as they are constructive :good: