note....
you must make a complete back up before proceeding
In this tutorial we'll walk you through on how to install Android M on your phone,but i think ive only seen it work on nexus 5, nexus 6,nexus player,and nexus 9.

if you want to know more about Android M click the link Android M


Note: The Android M developer preview has only been released for the Nexus 5, Nexus 6, Nexus 9 and Nexus Player right now, so if you do not have one of those devices do not try to flash the firmware or you will be in for a world of pain. Or at least you won't get very far. In any case, this process will wipe your device, so make sure you have a backup before you proceed.

How to get the Android M developer preview And Flash
If you want to know how to flash Android M, it couldn't be simpler. The Android M preview works just like any other Nexus factory image - simply download the file and flash it.
Prerequisites
Download ADB Tools and unpack the zip file
Download Android M preview for your Nexus (and unpack it in the ADB Tools folder):
Nexus 5 | Nexus 6 | Nexus 9 | Nexus Player
An unlocked bootloader
USB Debugging enabled
The relevant drivers installed on your computer
Install Android M on your Nexus now
1. Turn your Nexus off.
2. Press and hold Power and Volume Down to restart your Nexus to the bootloader (see image below)

Android,ANDROID M,NEXUS 6,NEXUS7,NEXUS 5,NEXUS9 ,NEXUS PLAYER ANDROID M



3. Connect your Nexus to your computer with a USB cable.
4. Open a Windows Explorer window and find the unpacked firmware you downloaded to the ADB Tools folder.
5. Double click the flash-all.bat file and let it do its thing.
6. Your Nexus will reboot and be running the Android M preview. If it doesn't, check the troubleshooting section below
Android,ANDROID M,DEVELOPER,NEXUS PHONES


Troubleshooting
if have any problem during flashing make sure you have USB Debugging enabled and an unlocked bootloader as described in the linked guide above.

any more questions should be referred to the comment section for help

HAPPY FLASHING
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