Out of all the devices out there that run on the Android operating system, Google’s Nexus lineup is the most popular to root. One of the main reasons for that is because developers love to buy Nexus smartphone and tablets and developers cannot do anything without access to the root file system as that is where all the changes are made.
Google’s Nexus lineup is also the first to get software updates because Google owns Android. The latest software update available is the Android N NPD56N Developer Preview 4 . Here is everything you need to root Google Nexus 9 on Android N NPD56N Developer Preview 4 firmware builds:
- You must have the Google Nexus 9 tablet to use this guide.
- The following guide is made for the Android N Developer Preview 4 with the NPD56N firmware build number. We do not know how much longer this rooting method works for after future software updates roll out.
BEFORE WE BEGIN
- Unlock the Developer Options menu and then turn on the USB Debugging Mode  on the Google Nexus 9 tablet before getting started with the guide so that the Android software can allow for some changes when connected to the computer.
HOW TO ROOT GOOGLE NEXUS 9 ON ANDROID N NPD56N DEVELOPER PREVIEW 4
- Download the SuperSU 2.71  on the computer so you can flash it from the custom recovery later.
- Download the TWRP Recovery 3.0.2 flounder  to the computer so you can install a custom recovery.
- Set up the ADB on the Windows computer  so you can flash the custom recovery.
- Install the ADB Drivers  on the Windows computer so ADB can run smoothly.
- Once you have followed the guide to set up ADB, you should have the ADB in its folder. Extract the TWRP and shift all the contents from the TWRP package to the same folder as the ADB so everything is in the one directory.
- Connect the Google Nexus 9 tablet to the computer with the USB cable that is available for charging the battery.
- Copy the SuperSU zip file to the internal storage SD card folder of the Google Nexus 9 tablet.
- From inside the ADB and TWRP folder, hold down the Shift key and right-click the white background where there are no files.
- Choose to “open a new command window here” from the new menu that presents itself after completing the step above.
- Type the first command in the command window: “adb reboot bootloader” and the Google Nexus 9 gets into the bootloader mode.
- Type the second command: “fastboot flash recovery twrp-3.0.2-0-flounder.img” and the custom recovery is now flashed on the Google Nexus 9 tablet.
- Enter the third command: “fastboot reboot” and hold down the hardware button combination that boots it into recovery mode as soon as it reboots so that it first-time boots into the recovery and thus eliminates the chance of the stock recovery wiping over your work that you just completed.
- The custom recovery that you just installed should now be loading. Tap on the Install button from the main recovery menu and follow the guidelines to browse through to the SD card storage and select the SuperSU zip file that you transferred there earlier.
- Confirm you want to install the SuperSU file by following the instructions on the screen.
- Choose the “Reboot” option from the menu after the flashing is complete and then “System” to reboot back into the normal mode.
In conclusion, that is how to root Google Nexus 9 tablets that are running on the Android N NPD56N Developer Preview 4 updates. The SuperSU is now installed and enabled, and you can see it from the Nexus 9’s app drawer as soon as it reboots back into the normal mode. Now you can start installing the apps that need root access to run. There is no reason to adjust any of the settings from within the SuperSU app to make it all happen. Just run the apps and then a pop-up message appears on the display asking if you would like to grant the app root access or not.