UPDATE 10.19.14: The full version of Android 5.0 has been released! Head to my How to Get Android 5.0 “Lollipop” on the Nexus 5 / Nexus 7 instead!

Google I/O just passed and one of the most exciting thing for most people was the revamp Android got with Android L. Android L is the latest version of Android and seems to be quite aimed at the design of Android for once. Smooth 60fps animations, subtle touches of color and shapes, revamping of the multitasking UI, and much more.

If you are anything like me, it’s at this point that you’re already asking how do I install the Android L preview? Well, if you have a Nexus 5 or a Nexus 7 (Wifi version only) you can do it right now by flashing the developer preview.

Before you jump on it, some caveats. First, this will erase your data so make sure to back everything up and get ready for that headache in general. Second, this is a developer preview so expect some bugs and things to just not work very well. If neither of those two things made you flinch in the slightest, then let’s get started.

Here’s how to flash the Android L Preview onto your Nexus 5 or Nexus 7:

I. Before You Begin

1. This will erase the data from your Nexus 5 or Nexus 7 so please backup everything to your computer (like photos, etc.) and make sure everything else is synced with your Google account).

2. These are previews and not fully functional, expect bugs.

3. I’m using Windows for this procedure as it’s what most will have to use. You can follow these same steps though for Mac (with changing the syntax for typing in commands).

II. Enable Developer Mode

1. On the device, go to Settings > About Phone.

2. Tap on Build Number repeatedly until it says you are a developer.

3. Hit back.

4. Tap on Developer Options.

5. Turn on USB debugging.

III. Download  and Setup the SDK & Android L Preview

1. Download the SDK Manager, install it, and open it (if that link doesn’t work, use this one).

2. Under tools, select SDK Tools, Platform-tools, and Build-tools.

3. Select everything under Android L Developer Preview section and click Install packages.

4. Accept the Licensing Agreement for all of the packages and click Install.

5. Download the correct version of the preview for your device below:

Nexus 5

Nexus 7 Wifi Only

6. Right-click the file you downloaded and select Extract All and extract it to your Desktop.

7. Take all of the files that are inside the folder and copy them to the C:/android-sdk/platform-tools/

IV. Flash the Android L Preview

1. Plug the device in via USB cable.

2. Open the folder android-sdk/platform-tools.

3. Hold shift on your keyboard and right click in a blank area in that folder, then select Open Command Window Here.

4. Type adb devices and you should get a serial number back (if you didn’t your drivers are not installed properly, head here for more help with that). If you did get a serial number, continue.

5. Type the following into the command prompt with hitting enter at the end of each line:

adb reboot bootloader

6. When the device reboots into fastboot mode, type the following into the command prompt with hitting enter at the end of each line:

fastboot oem unlock

7. Say yes on the device and this will unlock the bootloader (and erase your data). Then the device will reboot.

8. When it reboots, type the following into the command prompt with hitting enter at the end of each line:


9. This will now begin to flash the Android L image to your phone.

10. When it’s all done, unplug, and enjoy.

If you did this, what do you think of Android L so far?

If you want to undo this and get back to KitKat follow this video.

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  • Joe Richardson

    Hi, how would I get back to KitKat after installing this?

  • Jayden

    It is saying “permission denied” on the mac

    • During what step?

      • Jayden

        right when I entered “flash-all.bat”

        • .bat is for Windows, sorry for the confusion. Is there a .sh file in the folder where the .bat was instead? If so type that command instead.

          • pranav pant

            I read on bgr and they say to type ‘flash-all’. Should I type .bat at the end? I am using a windows 8.1 system

  • Britt

    After I type in flash-all.bat it just restarts the bootloader and windows tells me that flashboot.exe has stopped working. It then just reinstalls and boots into Kit Kat

    • Glitch. Uninstall the SDK and reinstall it. Reboot the computer. Try again.

  • Thomas

    Tried installing. Device frozen on a black screen with Google and an unlocked lock on it

    • Let it go for a while. Sometimes it just take a while. Also make sure you’re flashing the right device and at what point in the steps did that happen?
      If it is such good down the power button (or power and the volume buttons) to get it to turn off. Then turn it back on and try again.

      • Thomas

        it happened when I typed in flash-all.bat and it went straight to the boot loader instead of restarting. I’ve left the device for 5hrs and it’s still on the same screen. The device isn’t being recognised when I type “adb devices” in cmd

  • nishant

    phone blocked!first google and a unlocked lock appears then the nexus symbol(the four colors of nexus start dancing..:/

    • nishant

      yes after sometime it started and now it runs androi l..:)thank you

    • You bed to be patient it just takes a long time in first boot

  • dev shah

    mine says archive does not contain boot.sig and recovery.sig

    • It’s supposed to say that and then continue.

  • Dan

    I did do everting like in the video but when my nexus 7 restarted it restarted with kitkat.

  • Ron

    On the command window, when i’m hitting adb devices, it does show me a serial number with a messege “unauthorized” …

    • There’s pop-up message on the phone when you first plug it in via USB that you need to select yes on to authorize the computer.

  • Catalin Pena

    Thank you for this awsome tutorial,my nexus 7 is booting now,can’t wait to check out the new android :D.

  • Jared Gaskin

    when I type in flash-all.bat is says that it’s not recognized as a internal or external command… please help!!!

    • That means you are not in the right folder when executing it and it can’t see it. You need to make sure you open the command prompt by holding shift and right clicking in the folder where flash-all.bat is and that all of the files are in there. See step 7 in Section III.

      • Jared Gaskin

        Thank you!

  • Ben Morton

    after following all the instructions when i get to section IV #4 i type it in and all i get is
    abd server is out of date. killing…
    *daemon started successfully*
    list of devices attached

    and thats it no serial number, what do i do

    • Means you don’t have the drivers installed correctly. Google for nexus 5 adb drivers and install them.

      • Ben Morton

        Thanks! It took me a little bit but I got it! Great how to!

      • vivek shinde

        Same problem occurred with me. What to do? Kindly help me asap

    • Guest

      Same problem occurred with me. What to do? Kindly help me asap

    • vivek shinde

      Same problem occurred with me. What to do? Kindly help me asap.

  • Michael

    how about this…

    Michaels-MacBook-Pro:platform-tools michael$ ./flash-all.sh
    ./flash-all.sh: line 17: fastboot: command not found
    ./flash-all.sh: line 18: fastboot: command not found
    ./flash-all.sh: line 20: fastboot: command not found
    ./flash-all.sh: line 21: fastboot: command not found
    ./flash-all.sh: line 23: fastboot: command not found

  • Woody

    Great instructions!!! THANKS!!

    • pattilderrick

      my Aunty
      Allison recently got a nice 6 month old Jaguar by working from a macbook.this website C­a­s­h­f­i­g­.­C­O­M­

    • Glad to help!! Thanks for reporting it worked!

  • ricky

    hey i tried this and im about to do it for the third time, but i have a question, when one is installing the packages from sdk tools mine says 17 packages instead of 14 and in the video you just agree to the licensing to one package although there are 2 of them

    • Don’t worry about it and just continue. The packages could have been updated since I did this tutorial, it won’t effect the outcome.

  • Satish

    should the mobile be rooted before itsef to develop?

    • No it does not need to be rooted but during this process you’ll end up unlocking the bootloader.

  • maruf

    i’m not getting the serial key. plz help 🙁

  • kai123

    a dialogue box appears “flash-all.bat error…… windows is searching for solution”… what to do now??

  • Arun Joe Preetham

    It worked. Great!

    • Thanks for reporting back! Glad it worked!

  • jared

    worked great thnx man

    • Thanks for reporting back that it works still!

  • Antonio

    You’re Nexus 5 link doesn’t work.

    • Antonio


  • Abbas Almoumen


    • There’s a link for it on the Java site.

  • vivek shinde

    I am getting error while installing Packages as follows:
    Package ‘Intel x86 Atom_64 System Image, Android API L, revision 1’ depends on ‘SDK Platform Android L Preview, revision 4’

    Cant move forward.
    Kindly reply asap

    • Go back to the ask manager and install that package same way you installed the others.

      • vivek shinde

        i am not able to install any of the packages as after accepting the license ‘Install’ option doesn’t highlight.

        • Try deleting the SDK and reinstalling it from scratch.

          • vivek shinde

            Cant see my device on command of ‘adb devices’.
            I have installed all the required packages correctly. Switched ON USB debugging as well.

    • vivek shinde

      Cant see my device on command of ‘adb devices’.
      I have installed all the required packages correctly. Switched ON USB debugging as well.

      As u told me to uninstall and then reinstall sdk, i had done. I tried this reinstalling — checking — unstalling— again reinstalling– again checking. I have done this almost 4 times. But no result.

  • Jiří Bečka

    Is there a way how to get Lollipop to Nexus 4

  • Jasper Pye


    • Jasper Pye


    • Please click the link at the beginning of the tutorial in giant letters to be taken to the new procedure 🙂

      • Jasper Pye


      • Jasper Pye

        Still getting this error… Am I missing any files?

        • Did you do this tutorial? http://theunlockr.com/2014/10/19/how-to-get-android-5-0-lollipop-on-the-nexus-5-nexus-7-video/

          If so and you’re still getting the error, it might have something to do with the fact PowerISO is hiding the extensions so even though there is a boot.IMG its just showing boot. Google how to show file extensions in windows and do that then try again.

          • Wait scratch what I said about the poweriso and extensions since it did flash the radio. I’d suggest redownloading the files and putting them in that folder again and overwriting the current ones and see if that helps. Again though do the tutorial I linked to instead of this one.

          • Jasper Pye

            Right ok, this is where only having 150kB/s is not useful… Thanks for the help

  • phillbies

    The problem I’m having is uninstalling this preview. I bought this phone with the Android L preview installed and now I can’t flash to 5.0. When I type adb devices in terminal I get a serial number and ‘unauthorised’. All the fixes I read say to uncheck USB debug and recheck and a pop-up verification window will come up on the phone. But it doesn’t come up on mine. Other fix was to delete the dab-ket file on the phone but I can’t root either.

  • Dani

    Hi David,

    I have updated my nexus 5 device to android lolipop(developer preview).But now i want to restore the old kitkat stock rom.I am not sure how to do that.So please help me.