[ZTE Z7, Z7 Max, Z7 Mini] craagz:
Update:This tutorial might no longer be valid. It was meant for stock to lollipop beta. Now there is a stable update. Please check needrom website for latest updates.

Disclaimer: This is a lengthy process with downloads of up to 2GB or more required. This is based on my understanding of machine translated Chinese web pages and forums. This process was done on my own ZTE Nubia Z7 Max and it now successfully runs the Google Play Store on Lollipop. The Lollipop version is only 5.0. Please take caution in reading instructions, I take no responsibility if you end up with a bricked phone due to various reasons (improper downloads, power failure or thermo-nuclear war)

Note: You cannot easily go back to Kitkat after this process, please be sure that you want Lollipop. I have not faced any issues with the Lollipop Update, but just letting you know.

Background:

I have a Z7 Max with Nubia OS v1.59 (Kitkat 4.4.2) and I found out from another forum that a Lollipop version v2.13 (Official) is available. This is the process I followed:

Pre-requisites:

A ZTE Nubia Z7 Max (model: NX505J, Hardware Version: NX505JMB_A)

Windows PC (I did this on Windows 7 64-bit)

Drivers installed (When the phone is connected, it will appear under device manager as "Android Sooner Single ADB Interface")

Step 1: Upgrade to v 1.64

The update to V 2.13 can only happen from v 1.64. So first you have to get to v 1.64, if you are not already on it.

Download the v1.64 update zip (requires sign up at Need ROM)

Using the stock recovery update the phone through normal process

Copy update zip to SD Card

Apply update from SD Card etc. etc.

There will be no reset of data and apps, however you will lose Google Play Store/ Services connectivity and Root. It hardly matters as the phone will be reset in the next few steps.

Your phone must be on v1.64 now.

Step 2:Enable ADB and Factory ports

Open your dialer and input *#7678#

You will see two check boxes Factory[] and Adb[]

Check both

Step 3: Download the update file and update tool

Extremely Important: The update from Kitkat to Lollipop will reset the device as the partition is re-written. This is why the tool is required. (No the update cannot be flashed using a custom recovery)

Updater Tool

Download Link

Password: uslf

The v2.13 Lollipop update

Download Link

Password: 5u93

Note:

The above file might require you to sign up to Baidu and install their application to download large files. While registering for Baidu, you might be faced with a Chinese CAPTCHA. Use LINE Dict to draw the characters you see and solve the CAPTCHA

This will be a .tar file (use a utility like 7zip to extract the entire contents into a single folder "NX505J_CNCommon_V2.13")

Step 4: Using the update tool to update v1.64 to v2.13

Run the "nubia NX505J Updater V1.5.7.exe" installer

It will install the updater tool on your PC under "nubia NX505J Updater"

Run the updater tool from your All Programs menu

If you have all the drivers installed and ports enabled, the phone icon in the bottom will have a white tick mark in green bubble, else it will show an exclamatory mark (!) in red bubble. If red, please check drivers (use the driver installer that comes with phone, appears as CD Drive) and that ports are enabled

[IMG="Updater is green if all drivers are correctly installed and ports are open and phone is connected"]http://static.bbs.nubia.cn/forum/201503/06/153131ayp8p96d59yj58p5.png.thumb.jpg[/IMG]

Click the top button after "C:\Nubia Backup" and browse to the NX505J_CNCommon_V2.13 folder

Only when you have a tick icon and the folder selected, press the bottom button (to the right of "0/100")

This click will reset the device so please proceed with caution

The process will start and the phone will restart several times.

After this process you should have a working Lollipop Installation. (about 3-4 minutes)

Note:The process will stop at 92% for some time, don't worry about this, don't touch the phone or computer!!

I have linked to the Chinese official instructions from the Nubia marketing team below

Step 5: Using Temporary Recovery to Flash Gapps

On the Computer

Download the Recovery exe from This link here (Filename: Z7max_2.13_Android _5.0_CWM recovery.exe)

Running this file will give you a terminal screen with 10 options.

Press Option "2" - I don't know what it does, but the phone will reboot - Probably the bootloader is unlocked.

Connect your phone and copy to the SD card the Gapps package: I used the pico pack from Paranoid Android thread here

After copying the file to SD card, press option "5" - This boots the phone into temporary recovery

In the recovery:

Second option is to flash zip from SD card

Select your file from the SD card

Select the second line on next screen (This is probably - No, - Yes, Flash Zip options)

Gapps gets installed

Go back to main screen of recovery and select first option, you will be presented with two options, Reboot and Reboot Recovery, choose second option to get to Lollipop with Google Play store installed.

Root

Follow the same process to get root by flashing the SuperSu zip through the temporary recovery

Link to the SuperSu: Here

Reference

Lollipop Update Thread: http://bbs.nubia.cn/thread-419364-1-1.html

How to use the Update Tool: http://bbs.nubia.cn/thread-418088-1-1.html

Need ROM Page for v2.13: http://www.needrom.com/download/z7-max-2-13-android-5-beta_eng_chi/

Another recovery article (which I did not use): http://bbs.nubia.cn/thread-417675-1-1.html

Thanks

To Google: For all the wonderful Android ecosystem and For Google Chrome's translate option that helped me understand Chinese website (A few laughs at some of the translations)

The bbs.Nubia.cn forum where all the action happens

Need ROM for some of the crucial downloads in this article

XDA Forum for teaching me a lot about ROMs, Recoveries, and Roots

This is my first elaborate tutorial, I hope you like it. Please help out with "Thanks"