Prerequisites

First, be sure that the “Universal ADB Drivers” are installed. To be found here or here. the ADB command is available here. ADB documentation exists here. ADB won’t work if “USB debugging” was not enabled on the device. But it was, for sure, if as me your bricked it…

Then, get a TWRP Recovery image from here that can be installed without the need for a previous version. I took the TWRP 2.2.2.1 which is the only one that works fine with my Nabi 2 due to a Calibration issue with the other versions. As not available anymore from the page mentioned above (with all versions for Nabi 2), I had to take it from the Auto-Installer mentioned here (from the subfolder twrp/old).

Restore a Recovery

Now, connect the Nabi 2 on the PC and reboot the Nabi 2 in “Fastboot” mode:

• Press volume + and hold it while pressing also Power.
• Use Volume – to select “Fastboot” and select it with Volume +

Next, open a command prompt as admin on the PC and type:

Wait for the image to be loaded and reboot the device by pressing Volume + (to Select Bootloader) and next twice Volume – and once Volume + (to Select “Recovery Kernel”). The “Recovery” should now load (not be blocked anymore with a dead android) !

Upgrade to the most recent Recovery

One can now upgrade TWRP to a version which may only be installed on top of an existing one, such as the TWRP 2.8.5.0. I took the TWRP 2.8.5.0 v2 for KitKat here.

I went again into the “FastBoot” mode and uploaded the new Recovery image (TWRP 2.8.5.0) before restarting to enter the new Recovery Kernel.

Flash a stock Rom

And once in TWRP, I did “Backup” it on the SD card!

I moved next the SD card into my PC, I went to the folder \TWRP\BACKUPS\<id of my table>\<current date> and delete all the files in there.

Then, I downloaded the stock Rom 3.0.13 for KitKat (3013stock.zip) here and did unzip it in the backup folder before moving the SD back into the tablet.

I did reboot again the tablet in the Recovery and once there I did a “Restore” (keeping all items selected).

Once flashed, I did reboot the System (without installing SuperSU). After ~1 minute, the Logo started to spin and after ~2 other minutes the system started to initialize. After ~5 minutes, it was asking me to pick a language and configure the Wifi.

Et voilà FIXED !!!

Android is now 4.4.2, Build Bumber KOT49H, Product Version 3.0-release-keys.

My tablet was running:

• Fuhu Nabi 2-NV7A-US
• Version Android 4.1.1
• Kernel 3.1.10-g160ecc9-dirty
• Build JRO03C
• Product Version 2.3-release-keys

As I still have Android 4.1.1 (Jelly Bean) on my Nabi 2, I did get the Jelly Bean version of TWRP 2.8.5.0 mentioned here as I still have Android 4.1.1 on my Nabi 2.

Next, I took the Auto-Installer to be found here.

Then, I did unzip the “Twrp-recovery-JBNV7AUS-285.zip” into the Auto-Installer’s subfolder “twrp\new” and renamed it from “twrp-recovery.img” into “recovery.img” (replacing the existing img file).

Finally, I run RecoveryUpdater.bat and pick the option 1: “1. Install TWRP 2.3.3.0 for Nabi versions 1.9.37 (recommended)“.

It pushed the image I just copied into the subfolder “twrp/new” on my Nabi 2 and Bingo

1. The Nabi 2 had Rom 1.9.37 and TWRP Recovery Image 2.2.2.1.
   • I had a touch screen calibration issue with more recent TWRP. I didn’t try to most recent one however (E.g.: 2.6.3.0).
   • Original site of TWRP can be found Here.
   • All TWRP versions tested for Nabi 2 can be found here as well as the native Recovery Image from Fuhu.
2. Download the stock Rom 2.0.5 and unzip it from your PC onto a SD card under \TWRP\Backups\<device serial number>\abcdstock123, then re-plug the SD into the Nabi 2
   • This is the folder where TWRP did store my backup when I did root the device
   • All Stock Versions can be found here.
   • There should be 4 files: boot.emmc.win, boot.emmc.win.md5, recovery.emmc.win an System.ext4.win
3. Install PDA.Net, to be found here, if not available anymore on your PC.
4. Boot the Nabi 2 in recovery mode by pressing both the Volume + Button and the Power Button.
5. Press twice the Volume – Button to move to the menu “Recovery Kernel”
6. Press once the Volume + Button to enter the selected menu
   • it takes quite a few seconds to enter. Be patient.
7. Once entered in Teamwin (TWRP), select “Restore”
8. Then select “Using external SD” and pick the Stock Rom version 2.0.5 copied on the SD
9. Only restore System and Boot, but not your data!
   • I presume that all your data, if any, are in gmail, google+, etc…
10. Once the restore completed, reboot the system.
11. It will take some time to reboot, installing the various packages, etc…
12. Once back into Android, go to the “Settings” > “About” > “System Updates” > “Check now” for updates, “Download” it and install. Android will reboot at the end of that update.
13. This was actually the “first part” of the upgrade from the Stock Rom 2.0.5 to 2.3.11. With that first part, you are not yet running Android 4.1.1. You have to redo the step here above once more to install the “second part”.

Notice: I had an issue with the installation of the “first part”. I think that the “update” file was corrupted because I lost the Wi-Fi connection for a few seconds during the download. So, I had to restart the operation and it went then well.

I had a bigger issue when I tried to install the “second part” of the update. During the reboot, I got the red triangle dead Android picture… This is because I still had traces of rooted files on the tablet. The update din’t recognize some system files and refused to proceed further… Fortunately, there is a solution…

1. Download the fix OTA2.zip to be found here (named Part2 Work Around)
2. Copy the zip as is onto the SD card under \TWRP\ and re-plug the SD into the Nabi 2
3. Reboot into Recovery mode as explained previously
4. Now, instead of “Restore”, select “Install” and pick the file OTA2.zip from the “external SD”
5. As far as I am concerned, I did a “Wipe Cache/dalvik” after the installation..
6. Reboot the system.

Et voilà. The Nabi 2 is now running a fresh Jelly Bean with all kids’ favorite games re-installed from Google Play. Big big thanks to XDA-Developers’ community for providing such a great support!!

Notice: I am now running a US version instead of a UK version… But I don’t care as everything seems ok

I am not that happy about the upgrade…

For sure, the new Android interface for the parents is great. But there is no real change for my kids except that:

• It’s much slower to boot
• It freezes regularly while my kids are unlocking the screen immediately after the boot. The lock screen start to slide and then freeze in the middle of the screen. I have no choice but hard-reboot (keeping the power button pressed for some seconds)
• It also freezes sometimes while my kids are playing. Not often but still… I never had any issue in the past.

And a problem that I always had: when charging the tablet, the tablet always completely switch off and it’s a real pain to reboot it once charged. I always have to wait a bit (> 1 minute) after unplugging the tablet before being finally able to boot. Possibly due to the fact I am on 230V/50Hz and some kind of protection ? It looks indeed like the tablet refuses to boot because the battery is too hot…

My Tablet, a Fuhu Nabi II, is running Android 4.0.4. It has Bluetooth and Wi-Fi but no 3G. Since a few weeks, I have a “Belgacom Internet Partout Maxi” subscription, including mobile internet for free during the whole week (You have to go into your “e-Services” to modify your current “Mobile Internet Free Weekend” subscription and activate the “Mobile Internet laptop” as mentioned here). That’s why I was motivated to try my Belgacom dongle on my tablet.

First, I had to install PPP Widget on my Tablet.

Next, I did add the Widget on the screen. At that time, you will see a status “Checking access” displayed by PPP Widget and you will be prompted to grant it root access. If you don’t grant it root access, you will see a status “No root access” displayed. I suggest you to re-add the widget on the screen and grant it access or you won’t be able to use it.

The status displayed next by PPP Widget should be No modem found”. Click on its “Configure” button to set the Belgacom parameters:

1. Acces Point Name: internet.proximus.be
2. Username: (keep it blank)
3. Password: (keep it blank)
4. Dialing string: (keep it unchanged: *99***1#)
5. Check and set PIN: checked
6. Pin Code: enter the pin code of the SIM plugged into the dongle
7. HTTP Proxy: (keep it bank)
8. Disable USB device sleep: unchecked
9. Auto-Start Connection: unchecked
10. Automatic Re-Connection: unchecked
11. Automatic device detection: checked
12. Manual port selection: unchecked

Then reboot the tablet to start from a clean situation. Once back:

1. Disable the Wi-Fi.
2. Connect a USB cable to the tablet.  I did use an official Samsung USB adapter I bought for my Galaxy SII.
3. Connect the Vodaphone Dongle on the USB cable.
4. The dongle’s led should start to blink “green”.
5. When you are prompted by PPP Widget to “open PPP Widget when this USB devices is connected”, select “Use by default for this USB device” and click OK.
6. Wait for a few seconds. If nothing happens, unplug and replug the dongle. You should soon see the following status displayed by PPP Widget:
   1. Prepare device…
   2. Seach for port…
   3. Setup modem…
   4. Disconnected (and the button “Connect” should now be enabled)
7. Now, The dongle’s led should blink “blue”.

The Connect button of the PPP Widget will become “enabled”. Click on that button. PPP Widget will display the status “Dialing out…”. If it fails to connect, the status “Disconnected” will displayed. Otherwise, you should see “Connected!” and the dongle’s led should stay fixed “blue”. Enjoy !

If it does not succeed to connect, check that the dongle is still working on your laptop. Running the application “Vodaphone Mobile Connect Lite” on your Laptop, you will possibly get more details like “Sim card not found”, … Notice: I tried to use the latest version of the application “Vodaphone Mobile Connect Lite” on my Laptop (Windows 8.1) but got a message like “This program as compatibility issues”. I tried to run the Compatibility Troubleshooter, but it didn’t find a solution. Finally, although the application could start anyway, it didn’t detect the dongle. So I would recommend to use the software version available on the key itself.

You can also enable the log within PPP Widget, via the Configure menu.

Notice: if your tablet goes to sleep mode, you will be “disconnected” and the dongle will restart to blink “green”. When the tablet waked up, you should see PPP widget trying to re-detect the dongle and setup the modem. If it succeeds, you will be able to click on “Connect”. Otherwise, to unplug and replug the dongle.

The Nabi 2 is really great and fast.

• It connects to 802.11b/g/n Wi-Fi networks on the 2.4GHz frequency.
• It comes with Bluetooth 3.0 integrated (useful to connect with wireless headphones).
• It has 1GB of RAM
• It comes with 8GB of built-in storage of which 4.49GB are free
• It has a microSD slot to increase capacity (support 64GB microSD without issues).
• It has a mini HDMI out for playing videos on an HDTVs at up to 1080p.
• The battery can last up to 7h30 while running a video with screen brightness set to maximum and Wi-Fi switched on.
• It has a 2-megapixel front-facing camera above the screen.
• It has an accelerometer
• It comes with a thick red rubber silicone case that can be removed but is well protecting the tablet. Really let the kids play with it without much concern 
• It has a proprietary Monarch OS UI.

It’s built by a Los Angeles-area startup called Fuhu. You will find plenty of reviews on the web looking for “Fuhu Nabi 2”.

Unfortunately, it does not come with Google Play and generally speaking, Google Apps (“gapps”) may not be installed. This was really an hold-back for me as I have already a lot of paid softwares bought on Google Play for my Android phone that I wanted to reused them on that tablet. Fortunately, a known “exploit” of Android has been used to root the device and add all the Google Apps as explained on XDA-developers forum.

How to root the Nabi 2 is really best explained here (EDIT: see at the bottom for another improved package containing the “gapps”). Each manual steps are detailed here.

It’s really clear and did work quite well for me.. Quite well because it appeared that at the step where I had to select the gapps.zip file and install it, this one was not available… I think that the problem that I didn’t have a microSD card in the slot… I would recommend to have one plugged before rooting the device… What I did to solve that issue: I copied the file manually from my PC on a microSD card, I did plug the card in the device and I used the “Mount” menu of TWRP to make the SD card acessible from TWRP. Finally, I could select  gapps.zip on the external SD.

A last fright however. After the installation of the Google Apps (when TWRP says “Installation Complete!”) and before clicking “Reboot System” in the lower right, I noticed error messages in the logs: failed to mount \data.. Gasp !! I did try to mount it manually without success. As I still didn’t find a solution after one hour spent googling, I decided to reboot the device and pry…. And  fortunately, although it took a few minutes to restart and complete the update, everything appeared to be running really fine !

Next, I had access to all the Google apps, including  Google Play. I did installed successively on the Nabi all the application I already paid and installed in the past on my Galaxy SII…

There was however a remaining “issue” (neither blocking nor critical), the gapps package was giving a message ‘Android Upgrading’ on every boot. But there is a new package here that solves this issue. Simply copy it on your nabi 2 (E.g.: on the microSD – or download it directly on the internal storage). Next go to the recovery mode in TWRP 2.2.2.1 and install it:

• While the nabi is turn on, press the “Power off” button for a few seconds to get the “shutdown” prompt.
• Press next the “Volume +” and the “Power Off” buttons together for a few second to get the boot menu. You should see soon the following entries in the top left corner, is small fonts.
  • Boot normally
  • Fastboot Protocol
  • Recovery Kernel
  • Forced Recovery
• Select “Recovery Kernel” with the “Volume -” button
  • Don’t wait too long before starting to select this entry or the device starts to “Boot Normally”
• Confirm the selection with the “Volume +” button
  • The menu becomes brighter
• Wait for a some long seconds and here it is: the TWRP menu
• Select Install and browse to find the “gapps.zip” file.

site: http://www.nabitablet.com

xda-developers page: http://forum.xda-developers.com/wiki/Fuhu_nabi_2

Automated scripts: http://forum.xda-developers.com/showthread.php?p=36758895