[GUIDE] How to Root/Install ROMs on the TF300. Jelly Bean KitKat and Lollipop ROMs

[Gtanner00]

This guide supports the ASUS TF300T (wifi) model only
This guide supports the following ASUS Android 4.2 firmware numbers:
V10.6.1.15.3, V10.6.1.27.1, and 10.6.1.27.5.
This guide does not support the Android 4.2 10.6.1.8 firmware or lower. You can find out what firmware you have by going into Settings-> About Tablet and reading the “Build Number” If you do not have the right firmware, you will need to upgrade via OTA or manually.
Last Updated March 2015 (Just a little bit)

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I will preface this guide with a sincere thank you to Transformerforums user “Droidbound.” This a slightly modified version of his original guide here for the tf700 re-posted for the tf300. I was also inspired by Frederuco’s guides for the Tf101 here and wished that one had been available for me when I started rooting my tf300. Believe me I was extremely scared about everything at first

I want this to be a complete and up to date guide covering ROMing on the tf300, many of the guides found on the internet and xda are outdated or unmaintained. Some of them don’t even reference the latest ASUS bootloaders and the instructions in them can cause bootloops, bricking, or other problems.
I thought it would be especially helpful to add information relating to both jelly bean ROMs as well as the newer KitKat ROMs which have now become available from Cyanogenmod and Omnirom.

I hope this guide will make it a little easier for those users who wish to unleash the potential of this tablet but have no idea where to start. This is meant to be for inexperienced users who may be flashing for the first time.
If you find information I provide here to be incorrect or outdated, please do chime in!

And the standard disclaimer: I am not responsible if you misunderstand instructions I give here, if my instructions are wrong, if you forget to charge the battery and the tablet dies halfway through a flash or if your house goes up in flames.
YOU DO THIS AT YOUR OWN RISK

Part 1: Unlocking and Installing a Custom Recovery

First things first:
Backup everything on your tablet you care about to an external microSD or your PC. Don't worry about your apps. You can always install them from the Play Store.
This is just common sense. It is not inherently risky to flash custom ROMs. If you are following these guides and do not simply “flash without reading” there is little chance you can screw things up
Basically the process of flashing a custom ROM on the T300 involves three steps:
1) Unlock the bootloader using Asus' Unlock tool. (This allows us to gain the ability to install custom recoveries in the next step)
2) Install a custom recovery on the tablet (this is almost like a “mini operating system” which lets you modify the rest of the tablet in an isolated system. This includes making and restoring backups as well as installing ROMS)
3) Flash a custom ROM of your choice using said custom recovery. (I will include some links to notable ROMS as well as a description of each and installation instructions in the second post of this guide.


1. Unlocking the bootloader (See all the updates below these instructions: things have gotten a bit more complicated )

Please make sure that your tablet has a fairly full charge on it (or is connected to a charger) whenever you are doing these steps. It would be a terrible tragedy to follow all the steps correctly only to “brick” the tablet when the battery dies in the middle of installing something.

• Make sure "USB debugging" is checked in Settings > Developer Options (if you don't see it, go to About Tablet and tap 7 times on Build Number)
• Go to Asus website: ASUSTeK Computer Inc. -Support-
• Select your device (ASUS Transformer Pad TF300T), choose "Android" for OS and look for the "Utilities" on the resulting page.
• Download the “Unlock Device App: Unlock boot loader.(Only works with TF300T 4.2 JB OS)”
• The tool downloads as a .rar file which is an archive you have to decompress. 7zip is a free and very good Windows tool that will do it for you
• On your tablet, in Settings > Security check "Unknown Sources"
• Copy the .apk you extracted from the .rar archive to your tablet.
• Find the apk in your tablet's file browser, tap it and let it install
• Open the app and follow the instructions. You will loose your warranty as soon as you click "I agree".

*Update* It seems that users sometimes have problems with the unlock app due to Google labeling it as "less secure" There is a Google Account setting to change that should fix things right here. https://www.google.com/settings/security/lesssecureapps

*Update* July 2015: And another wrinkle... It seems to be pretty consistent now that the Unlock Tool hangs on the Google account password step. I suspect something changed on the Google side. It probably doesn't allow the tool to check/compare the password anymore. There have been quite a few security changes lately and the unlock tool never gets updated so I suspect that Google now is blocking access by the tool to it's servers.
The work-around is easy enough: Delete the Google account from the tablet (Settings > Accounts), then run the tool again. If that doesn't do it, do a factory reset from Settings, reboot and during the initial setup establish a WiFi connection but skip the google account setup, then run the tool

*Update* December 2015:
So it looks like Asus decided to remove all the old Transformer support drivers and firmware off their site for some regions. That includes the unlock tool. Luckily for us, We have a copy of the tf700 v7 app saved from destruction by Kevinthefixer (let's all give Kevin a round of applause!) \
UnLock_Device_App_V7
I can't test this but I am told it works the same way as always. If you run into trouble try the trick posted above that mentions removing your Google account. Otherwise post in this thread and someone will be able to help you out.
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To check if you are unlocked, boot the tablet and read the tiny script. It should say:
The device is unlocked.

This can be a 5 Minute operation that goes without a hitch or a very frustrating experience with lots of error messages. There is no definite rhyme or reason for this. For some people it works like a charm, for others it works after 15, 25 or 35 attempts, for some never.... This problem is widely discussed on several forums. For now I assume it goes ok.

To check if you are unlocked, boot the tablet and read the tiny script. It should say: This device is unlocked.

2. Installing a custom recovery on your tablet
I highly recommend you choose TWRP as your custom recovery.

This is the trickiest part of the whole process. To push TWRP to your tablet you need to set up "Fastboot" between your tablet and your PC. Fastboot is a protocol that enables you low level access to your tablet.


Practice/Background
Power down your tablet and disconnect it from the dock
Push and hold the Volume Down key (left side of the rocker) and the Power key at the same time. Let go when you see the tiny script. Read it and it tells you that your tablet is now in fastboot mode
You are now in the JB bootloader menu where you see 3 icons: RCK, Android, Wipe Data
IMPORTANT! You should have three icons in your bootloader. If you have 4 do not proceed from here. You need to upgrade to the newest 4.2 bootloader

RCK - (which should be flashing) is your recovery (the stock recovery at this point, but once TWRP is installed this is one way to get into it)
Android - is your system, selecting it boots you back to into your ROM. This is what is known as a cold boot.
Wipe Data - stay away! Especially with custom software installed never, never use this option!
To toggle between the three icons use Volume Down, to select one use Volume Up. Try it but do not push Volume Up when the 'Wipe data' icon is flashing!

In case you ever get into a bootloop from doing this, we now have a very helpful guide HERE for getting out f it.

Now you need to install the fastboot on your PC (I will only deal with Windows instructions as I cannot vouch for any OSX or Linux guides. You can Google methods to install fastboot drivers as there are many different ways to accomplish the same thing)
For Windows users I recommend the 15 Second ADB tool [TOOL] [WINDOWS] ADB, Fastboot and Drivers -… | Android Development and Hacking | XDA Forums (easy instructions on XDA thread page)
If you have OS X I cant provided any assistance but here is a reputable guide [GUIDE] Set up ADB and Fastboot on a Mac eas… | Android Development and Hacking | XDA Forums
If you have Linux, I think most distributions have the packages for ADB and Fastboot installed out of the box.

• Run the Installer executable file and answer yes to all the prompts.
• IMPORTANT: Dont forget to agree to installing device drivers or you likely wont have success with any of your commands.

• Boot the tablet into fastboot mode and connect it to your computer via the original USB cable
• In Windows Explorer navigate to the folder that contains your adb.exe and fastboot.exe. For the 15 second tool this is a folder in your C drive directory
• Press Shift + right click and select "Open command window here".
• In the command window on your PC type:

   fastboot devices

• If that command returns a string of numbers and letters, you are good as gold.
• If it returns: "No devices found", fastboot is not working - yet - and you have to troubleshoot.

Getting the correct drivers working can be the hardest part of this exercise. If your computer does not "see" the tablet in fastboot, you may have to google another method that will work better for your system. In Win8 you seem to have to disable a "Windows Driver Verification" setting in system settings. I have embedded a video below which goes over that procedure as well as using another tool called Minimal Fastboot and ADB (Credits to XDA and also Droidbound for originally linking it)


Let's assume everything is good:


•On your computer go here. [RECOVERY] KANG TWRP TF300T 2.8.x.x@AREA51 J… | Asus Transformer TF300T | XDA Forums
This is a special recovery made for only tf300s on the 4.2 bootloaders mentioned at the top of this post. This is not the "official version, rather a "kanged" version with bugs ironed out. It is known to be much more stable than the official versions.

Download the latest build available from the link in the second post on XDA. It should come through as a .img file

• Rename the file to twrp.img (or whatever you like but remember what it is called) and place it into the same directory as your fastboot.exe in the ADB Fastboot Tool folder. For example, my directory was C:\Program Files (x86)\Minimal ADB and Fastboot. Make sure your computer is showing extensions properly so that you don't accidentally have twrp.img.img
• Again check the connection to the tablet with:

fastboot devices

If you get the connection, in the command window type:

fastboot -i 0x0B05 flash recovery whateveryounamedit.img

This will flash the recovery to the recovery partition
If it is successful you will see something like this:

C:\Program Files (x86)\Minimal ADB and Fastboot>fastboot -i 0x0b05 flash recovery twrp.img sending 'recovery' (6448 KB)...
OKAY [ 1.856s]
writing 'recovery'...
OKAY [ 6.624s]
finished. total time: 8.487s

If you see the word finish then the recovery has been flashed, but you need to reboot into android for it to take affect.
Use the command:

fastboot reboot

and let the tablet boot up normally.
Or if that doesn't work you can hold the power button.


Open Recovery and Create a Nandroid
Your almost there! You are now on the stock ROM with a custom recovery installed.
Power the tablet down and boot into the bootloader menu with Volume Down and Power buttons.
With RCK flashing, push Volume Up and you should boot into TWRP. Familiarize yourself with the many options of the touch based interface without executing anything yet. TWRP is very user friendly. You basically cannot do anything of consequence "by accident", so don't be shy.

twrp 2.5.jpg



Touch "Backup", leave the default selection as they are and swipe the button to create a nandroid (a backup) of your current system.
This is a very healthy habit to develop: You always want to have a nandroid of your last working system squared away so that you can do a simple restore if you flash something that does not work, or something goes wrong during a flash. With a working recovery and a good nandroid you are minutes away from a working system if you soft brick your tablet. These backups are located in your Sdcard/TWRP directory if you ever need to remove them from the tablet or delete them. These backups are typically between 3-6GB and only include your operating system, preferences, and all applications. They do not include your files, songs, pictures, movies, etc. If you want to restore a Nandroid you can easily do so by touching the restore button in TWRP. This will "wipe" any previous data and replace it with the data included in your backup. Note: any files, pictures, etc. which are not backked up will not be touched when restoring nandroid.


You can out of recovery by selecting Reboot and System on the following screen.


OK, so this concludes the first part of my guide on ROMing TF300s. I will continue this guide below with additional sections on using TWRP and installing ROMS.

In the meantime, feel free to post below and ask questions.

[Gtanner00]

Update: I recently edited this post to consolidate the ROM links since some have been dead for a very long time since writing this. I have now listed them in order of current popularity.

Installing a ROM

This guide assumes you have either a) followed the post above on unlocking and installing a recovery or b) already have a working TWRP 2.5 recovery on a compatible 4.2 boot loader.

Making some decisions
before you start flashing ROMs we need to go over some of the choices you have at your disposal and some new vocabulary

Jelly Bean vs KitKat, Lollypop and Marshmallow
All custom ROMs are based on a certain version of android. Currently there is a selection of 4.2, 4.3 (Jelly bean), 4.4 (KitKat), Lollypop (5.1) and Marsmallow (6.0) Roms that have been created for the tf300. Using the TWRP Recovery you can install any of these ROMS. There are reasons why some users will prefer the latest and greatest while others will want to use a modified stock ROM
Most of the ROMs listed in this and the following post are compatible fully with all keys on the keyboard dock.

Stock Based vs AOSP
ROMS for the tf300 come in two distinctive types.

​1. Stock based ROMs These are based on the existing ASUS firmware and therefore run android 4.2.1. While these may look identical to the "stock" (default) firmware, the developers spend a lot of time tweaking and optimizing things behind the scenes. These ROMs often come with special kernels which can increase performance and allow "over-clocking" of the cpu.

2. AOSP based ROMs These are ROMs that typically come from the "major developers" and are meant to bring newer versions of Android based on the "Nexus" device firmwares to a large variety of different devices. This means that the ROM will have a standard look across the many different devices it supports. AOSP stands for Android Open Source Project if you're wondering.

Nightlies vs Stable.
Many of the AOSP ROMS have a program for updates called "Nightlies" This functions the same way as OTA updates that come from ASUS except they are available every day, or every few days. if you choose to install nighties you do not have to install every single one, you do not even have to install them in chronological order. They are simply there to make it easier for you to update the ROM. upgrading a nightly does require a clean install and it is applied in nearly the same manner as a regular OTA (over the air) update.

Alternatively some ROMs offer "stable" or "snapshot" builds which are nighties which have been designated as stable turning points in the development process. This is not to say that "nightly" builds are not inherently stable (there is no difference between many of the nightly builds and the stable ones) but there is a possiblility that a nightly could temporarily "break" something like gps or Bluetooth and you will simply have to revert to the last working nightly.

"Clean" vs Dirty Flash
Typically when you install a ROM you will want to have a clean start which means starting with a limited amount of data. This is similar to a factory reset on "stock firmware" except it will only wipe your applications not your files, pictures and other personal data.
You are required to Clean Flash for any AOSP ROMs and it is recommended for Stock based ROMs. It simply makes sense to spend an extra 30 minutes making sure you get the fastest, most stable experience possible.

Here is a link to my guide with step-by-step instructions on how to backup and restore all your data for a clean flash i recommend you read it before continuing.
[GUIDE] How to backup and restore apps when making a clean ROM flash

A 'dirty flash" as it is sometimes refered to is usually reserved for simple ROM updates. It involves flashing directly over your existing ROM and wiping the cache, and dalvik cashes afterwards.



A Note on GAPPS (Google Apps)
AOSP ROMs require an additional file to be flashed along side it called GAPPS which contain the google system apps which include the Google Play store at the bare minimum. I recommend always using the GAPPS Package linked from the ROM page. If you cant find a GAPPs Package they are usually pretty universal but make sure you get one that is compatible with your android version (only install 5.x packages on 5.x ROMs) notable GAPPS distributors are Banks, Cyanogenmod, and Paranoid Android.
A few words of warning:

• Never download a ROM meant for another device, or even another boot loader version. Always install ROMS from the XDA developers tf300 Android Development Section here http://forum.xda-developers.com/transformer-tf300t/development
• Always read the first post of every ROM you want to flash as well as some of the most recent comments as to become familiar with the current development state (what is/ is not working etc.)
  
• Make sure you have a nanroid backup of a working system which you can go back to if anything goes wrong. Always keep a copy of at lease one backup off the tablet.
  
• I have personally tested most of these ROMs at some point in the past. I do not guarantee that they are they are functioning the same way now as they did then. You flash at your OWN risk

How to Flash

1. Download the necessary files (the ROM, Gapps etc.) and place them somewhere on your tablet or on a micro sd card. (if you use a card make sure it is formatted so that TWRP will recognize it)
2. Reboot into TWRP recovery. If you are doing a clean flash select the Wipe panel. Swipe the blue arrow across the screen to factory reset. Return to the main menu
3. Tap the Install button and select the ROM and swipe to confirm the flash.
4. Flash any GAPPS if necesary.
5. Wipe Caches and Reboot. (reboot will take longer than usual)

​So there you go! You just flashed your first (or maybe not) ROM.

The ROM List

These are only a sample of the ROMS available to the tf300 but these are the main ones

Stock Based

CROMI-X 5.X [ROM]★●[TF300T/G/L/201/301][CROMi-X 5.3][ROM2SD | ODEX/DEODEX 10.6.1.27.5][01/18]●★ - xda-developers
This is undoubtedly the most popular and stable stock ROM for the tf300 device. It included a customization installer with choice of apps, kernel, and other tweaks. has the ability to install Xposed Modules like Gravity Box which provide loads of extra modifiable features in a single app.


AOSP Based: Note Most developers have stopped developing for the tf300 with the exception of Timduru (Katkiss) There is a lot of great ROM projects available that are no longer being actively maintained. There is nothing wrong with these older ROMs but they are considered "Legacy" and therefore don't get much developer support and zero updates.

Katkiss 6.0 The only active ROM as of this update. Timduru has put a lot of work into optimizing this device and still supports the forum page on Xda. You can also find pages for other versions of this ROM built on different Android versions.

CyanogenMod The original AOSP ROM. maintains a true to Nexus stock experience with many small extra customization features. Has nightly and stable versions based on various versions of Android

OmniROM 5.1 Similar to CyanogenMod with builds as new as January 2016.

Again there are quite a few other ROM selections of various Android versions but I haven't linked them since their pages are no longer active.

Happy Flashing
GT

[Gtanner00]

Update: This post is now depreciated since I have consolidated the remaining semi-active ROMs into the previous post.

Installing Android 4.4 "Kitkat" ROMs

This post will cover installing ROMs that are based on the latest 4.4 Kitkat version of Android.

Please read the above post before proceeding in order to become more familiar with the process of flashing and ROM and some of the vocabulary i will be using. Let's get started!

Benefits of Kitkat and Lollypop:
Android Kitkat was built from the ground up to be optimized for "low speced" or aging android devices. it has a very low RAM which should theoretically improve multitasking performance. Android Kitkat includes redesigned white status bar icons, and support for "Immersive" navigation mode in apps. There is also a new ART Runtime built in to Kitkat that should increase the overall smoothness and speed of the device. (more on all this later)

Android Lollipop built upon the framework of Kitkat and now includes ART as the default runtime which can increase performance. Android Lollipop was also a huge design release for google which introduced new animations and formats referred to as "Material Design." Its a design that is very beautiful but takes some getting used to.



ROMS

Cyanogenmod 11 (nightly and snapshot versions) [ROM][4.4.2][OFFICIAL] CM-11.0 for tf300t - xda-developers

OmniROM 4.4 nightly builds and homemade builds (which include multiwindow) maintained by developer "Scanno" [ROM] [4.4.2] [OFFICIAL] OmniROM for the TF300T [2014-02-08] - xda-developers

CROMBi -kk ROM ROM★★★TF300 KitKat 4.4.4-C… | Asus Transformer TF300T | XDA Forums a collaboration between Cromi-x developer Sbdags, and CMB ROMS developer Ij50036. This includes all of the installer options and speed from CROMI-X in a CM11 based ROM.

ZOMBi -X, Another collaboration from the CROMI Team. This one is based from the OMNI-ROM sources rather than Cyanogenmod. Includes different features and speed tweaks than CROMbi.[ROM]★[TF300 KitKat 4.4.4][ZOMBi-X OMN… | Asus Transformer TF300T | XDA Forums



*NEW* It's been a while since I updated this post. Since then there is a wide selection of ROMs built from Android 5.1 and they have become quite stable.

Katkiss 5.1 [ROM][LP 5.1.1_r1] [ KatKiss - Lollipop #023… | Asus Transformer TF300T | XDA Forums

OmniROM 5.1 Nightly Homemade builds by Scanno [ROM] [5.1.x] [PRE-NIGHTLY] OmniROM for the … | Asus Transformer TF300T | XDA Forums

Official Nightlies for CM12 (5.0) [ROM][5.0.2][OFFICIAL] CM-12.0 for tf300t | Asus Transformer TF300T | XDA Forums

Zombi-Pop ROM built and tweaked from OMNI. A collaboration between developers Hardslog, Lj50036, and Sbdags [ROM]★[TF300 LP 5.1.1][ZOMBi-POP OMNI … | Asus Transformer TF300T | XDA Forums



What is ART
ART is an experimental Android Runtime that was introduced in Android 4.4 Kitkat. you can read more about what it is here. ART is supposed to be the future of android and provides a smoother faster experience on Android by running apps natively (like on Apple devices) rather than using a virtual machine (If it sounds complicated that's because it is, but you don't need to know anything about it to enjoy it. Please know that ART is currently unsupported by Google, and while it is completely safe to run on your device it could have app incompatibilities.

*Update* ART wasimproved upon and released as default in android 5. All apps are now fully compatible with it.

That's all folks
Again, let me know if you'd like anything changed or improved.

[rspierenburg]

So once you get to this point, is the install for different types of ROMs (eg Cromi-x vs Cyanogenmod) pretty much the same?

[Gtanner00]

So once you get to this point, is the install for different types of ROMs (eg Cromi-x vs Cyanogenmod) pretty much the same?

Yes, and no. For all jelly bean Roms eg Cromi, and CM 10.2 the install process is the same for each. It is a bit different for KitKat Roms so I will go into that process another time.

It is recommended that you do a factory reset in TWRP which will wipe all of your apps and settings (all of your personal media and files are not wiped, and you can restore apps from the play store or a backup later. I think I will also add a section about data backup and restoring for people who want to make clean installs.

If you follow the first post then you are ready to install cromi from here. http://forum.xda-developers.com/show....php?t=2425390

Sent from my Nexus 4 using Tapatalk

[Gtanner00]

Just updated the 2nd post with Jelly bean ROMs and linked to my new post about backing up and restoring apps.

More to come in the next few days so check back soon.

[droidbound]

Great job @Gtanner!!! I think I'm going to steal some of your ideas

[Gtanner00]

Great job @Gtanner!!! I think I'm going to steal some of your ideas

No problem. Thanks for the inspiration and motivation to start.

Sent from my Nexus 4 using Tapatalk

[rspierenburg]

So I just completed the first section of your post and got TWRP setup. It was very easy to follow, very well written. One comment is that I tried to use the fastboot command the first time to get twrp.blob installed and it wouldn't work. I tried it a second time but this time with administrator rights and it worked without a hitch. Not sure if this was just a hiccup or something that should get noted in the post perhaps? In any case, I love this post it worked like a charm. Now on to Cromi-x whoot!!

Edit - Just finished installed Cromi-X and I couldn't be happier. Thank you Gtanner00, sbdags and everyone else who had a hand in this.

Rob

[Gtanner00]

So I just completed the first section of your post and got TWRP setup. It was very easy to follow, very well written. One comment is that I tried to use the fastboot command the first time to get twrp.blob installed and it wouldn't work. I tried it a second time but this time with administrator rights and it worked without a hitch. Not sure if this was just a hiccup or something that should get noted in the post perhaps? In any case, I love this post it worked like a charm. Now on to Cromi-x whoot!!

Rob

Nice. Great to see it works for someone new. When you mean admin rights, do you mean a windows administrator user, or right click and running the program as an administrator?

Have fun with cromi. Remember you can run the installer as many times as you want to figure out what tweaks you want. Are you trying for a clean flash?

Sent from my Nexus 4 using Tapatalk