Google has confirmed that its new software, which was announced at I/O 2015 event as Android M, will be called Android 6.0 Marshmallow and its developer preview has been made available to devices like Nexus 5, Nexus 6, Nexus 9 and Nexus Player.

The search giant is expected to officially make the firmware available by the end of September but it has released the final developer preview, which means owners of select devices can run it before its official launch.

Owners of Nexus 5, Nexus 6, Nexus 9 and Nexus Player will get over-the-air (OTA) update for developer preview 3 if they are already on either developer preview 1 or 2. However, owners of these devices who haven't installed preview 1 or 2 will have to install preview 3 directly.

Step-by-step guide to install Android 6.0 Marshmallow preview 3:

1) Download the ADB tools and unpack the zip file (Note: There is separate factory image for each device: Nexus 5, Nexus 6, Nexus 9 or Nexus Player).

2) Extracted ADB tools and factory image should be in same folder.

3) Device should be started in fastboot mode.

To activate fastboot mode, press power button and volume down button simultaneously for some time. Double click "flash-all.bat" file once in fastboot mode and the device will reboot automatically before Android 6.0 Marshmallow preview 3 is installed successfully.

(Note: Users are recommended to back up important files in their devices and ensure at least 50 percent battery before installation. Only individuals, who have knowledge of using factory images, should install the developer preview)