With each version of Android that is launched, we see a greater momentum for Google to protect the data of its users. So much so that in the latest version Android 5.0 Lollipop a certain standard was established that would have to be followed, although some follow it more than others. In short, the terminals with Android Lollipop seriously would have to come encrypted by default.
When we met this news, we were struck by doubts about it. Having the encrypted data requires extra processes that go for the decryption of each data we access or the encryption of a new file that is created. This could lead to a loss of performance in the device and in both the Nexus 9 and the Nexus 6, this small loss was noted.
Deciphering the Nexus 9 is easier than it seems, we explain it to you
If you have a Nexus 9 and want to recover that small, although noticeable, loss of power of your tablet, we explain how. In this tutorial we will explain how to completely decipher our Nexus 9.
IMPORTANT: In the process you will lose ALL your data and files stored on the device. Safeguard what matters most to you before starting the tutorial.
For the process we will need the factory image of Android 5.0.1 of the Nexus 9 through the Google developer page. Unzip everything and we will have a folder with several files inside. We also decompress the other compressed file we found. Everything would be just like that, with 6 «.img» files. Here we will also have to copy the files ADB and FASTBOOT. Of course, we will have to copy the file that will skip the encryption of the tablet, in this case, a boot.img modified by an HTCMania user where it also explains the process to follow.
Download Android 5.0.1 Nexus 9 Factory Image (LRX22C)
Download ADB and Fastboot files (Windows) (Linux / Mac)
Download modified boot.img
In the folder with all the images and the ADB and Fastboot files, we will change the name of the original "boot.img" to "bootoriginal.img". Now we copy the modified boot.img in the folder and that's it.
The process to follow is very similar to when we install a factory default image, only here instead of using an executable, we will write the commands ourselves. If you follow them to the letter, you will have no problem.
The "Android" folder would look like this
Once we have the folder with the six files ".img" and the files "adb" and "fastboot". We can start entering the commands.
First we will have to place ourselves with the terminal in the folder where everything is. In Windows you will have to press and hold the "Shift" button and press with the right button inside the folder, here will appear «Open command window here«. Press and go. In the case of Mac OS X or Linux, we recommend putting the folder on the desktop and putting this command in the terminal "cd Desktop / foldername" for example, the folder called Android ("cd Desktop / Android").
Once this is done we will have to make sure that we have the USB debugging mode activated. To make sure we connect the tablet to the computer and type this command.
adb devices (in Windows) || ./adb devices (on Linux / Mac)
Here your device will have to appear as connected. If it does not come out, reconnect the tablet and allow the USB debugging union accepting the window that appears.
IMPORTANT: You will have to have the bootloader unlocked. To unlock it you will have to enable the developer options (same process as to enable USB debugging) and activate OEM Unlocking. Having done this, with the device in fastboot mode (Vol + and Power) we write the following command and follow the instructions on the screen.
fastboot oem unlock (Windows) || ./fastboot oem unlock
Now we leave you the commands that you will have to execute in the terminal. Not to write twice, remember that in Windows it is not necessary to put «./» at the beginning of each command. Id entering the commands as the terminal ends with each of them. Here we go! (With the first command we would enter the fastboot mode, you can also do it by pressing «Vol + and Power» and you will save that command, although I think it is more comfortable).
adb reboot bootloaderfastboot flash bootloader bootloader-flounder-3.43.0.0114.imgfastboot reboot-bootloaderfastboot erase systemfastboot age vendor vendor.imgfastboot reboot
Once the reboot is finished a green android will appear moving the antennas, it will reboot and start as usual. When we have entered all our initial configuration data, we will Settings> Security and we will see how the possibility to encrypt it.
If you have any questions, leave it in the comments that we will try to answer as many as we can.
Remember that Free Android does not take care of any problem on your device. We have done it and that's why we bring it.