Backup and Reset Nexus 4: Cracked and Locked Screen

Story of a Flaw

Nexus 4 has an invisible design flaw: the back side of a phone is just glass, which, while looks pretty to some, makes it slide down and fall from pretty much any surface. Another unfortunate caveat is the curved unprotected glass on the front. If the phone falls down, it’ll most likely crack…

And here I present a 20 day old brand new Nexus 4:

nexus screen

After the unfortunate flight down, the screen is done and stopped responding to any tapping/touching. In addition the screen is locked with a gesture pattern. The phone is not rooted and with a locked bootloader: exactly how it comes from Google.

Android iTunes

At this point I need to back it up and factory reset the phone in order to ship it safely for repairs. Since Google is moving towards Apple’s “lock down and control” system design, the phone can’t be just plugged in via USB to back up its files (e.g. via USB Mass Storage), now days there is MTP. As Google puts it:

“We did it because we wanted to be able to merge the “public shared storage” (i.e. for music and photos) with the internal private app storage.”

Yea, ok, while it does have a technical merit, it really brings user experience closer to the “iTunes level”, not as bad yet, but quite close. In any case, since the Nexus 4 screen is locked, Android iTunes complains that until that screen is unlocked it won’t be showing any files. Yea, thanks for the security Apple.. I mean Google.

Unlocking the Screen

There is a great tool written by Alexanre which allows to control an Android device remotely from Mac/PC. In other words a regular keyboard/mouse could be used to control the Android device. The tool is called Android Screencast. The only caveat, the phone needs to be rooted in order to be controlled by this tool. I got to see the phone’s screen on my Mac:

android screencast

In order to make Mac keyboard to work I need to do “chmod 777 /data/dalvik-cache” as root (e.g. “su”), but the phone is not rooted, bummer. The tool is great though.

Btw, if the phone was rooted, I could simply do: “adb shell rm /data/system/gesture.key” to get rid of the screen lock.

Backing Up What’s Dear

One thing I knew I could do for sure is to backup the “sdcard”. I knew this because of two things: I have “USB Debugging” on, which means I can use adb, and “sdcard” is not owned by root, which means it can be “pulled”/”read” by adb. Hence the first step is clear:

./adb pull /sdcard/ /destination

At this point all the pictures / videos / music, etc.. are backed up. Now I need to backup my SMS, contacts, etc.. Information that lives in Android “databases”. For example contacts usually live here “/data/data/”. Which can’t be simply “pulled” as pitures, since they are protected, and hence cannot be read by adb directly.

Another tool to the rescue: Moborobo. The only caveat it is a Windows tool, and in order to install it I needed to power up my virtual box. The tool is pretty neat and quite powerful. Unfortunately all it could backup for me was SMS, everything else failed, but it is one step further nevertheless + I have most of my contacts gmail synced. Apps would be nice to backup, but they can be reinstalled manually later on.

Waving Goodbye or The Factory Reset

Now the interesting bit: the factory reset. It was not really straightforward, since most of googled instructions either talk about doing it from within a phone by tapping through settings, which is not an option in this case, or by using Home / Back buttons which are also a part of the screen that does not work. But after some minutes “the way” revealed itself.

Firstly the phone needs to be rebooted in “Recovery mode”, which can be done through fastboot, in case “USB Debugging” is not enabled:

Disconnect the phone. Power it down (by holding the Power button). Reboot into fastboot mode by holding the Volume Down button and Power:

fastboot start

The “Recovery Mode” is two Volume button clicks away (confirm with a Power button once the mode is selected):

fastboot recovery

In case “USB Debugging” is enabled, the easier way to get to this step would be via adb:

./adb -d reboot recovery

Which will boot into:

recovery mode

From here press and hold Power button and then press Volume Up, which will get into:

android factory reset

Now all that needs to be done is to mentally wave good bye to all the data and confirm the reset:

confirm factory reset

And the Award Goes To…

All the pictures are courtesy of my good old Nexus S, which has fell down countless number of times over the years and have a couple of scratches on the back. Yes, “they” knew how to build phones for real in the good old days..

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  1. MTP actually gives you _more_ freedom. Prior to its adoption, you had two partitions on your phone: private and public. The rub here comes in the form of running out of space on your public partition, but the phone still reporting ample free space. The ample space here is part of the private partition, thus the frustrating state of “you can’t do anything about it”. MTP solves that by safely enabling you access to _all_ the space. Some os’s do a better job of playing nicely with that type of connectivity while others don’t. gMTP solved my Nexus 7 – Ubuntu 12.04 connectivity issues, for example.

  2. @andy,

    I do get MTP’s technical merits, and I mentioned that. What I dislike about it is the user experience. It does give you more space, not freedom.

    When you plug your phone in, and have access to everything as it was a thumb drive, it’s freedom. When you have to choose between two confusing modes (MTP/Camera) and then connect and get “some” files in a horrible explorer which also blocks you (and will do more controlling things in the future) is quite another. Not much freedom there.


  3. Thanks you!!

  4. Similar experience, only three days after getting phone and didn’t even have SIM card yet! I had set up my gmail, so this would be perfect for me except I cannot get the last step to work. Unfortunately, holding power and volume up just powers off the phone. In any case, thanks for posting this!

  5. Got it! The trick is to hold power and then press volume up, rather than holding down both power and volume up! (I.e., if you don’t let up on volume up, then it will shut down before going into the right mode.) Thanks!!!

  6. Just wondering where you’re sending your bust Nexus for repair – I just got a Nexus last week. And last night I dropped it…

  7. @Marcus,

    Contacted LG Technical Support and they gave me the address to send it to. If I did I had to pay for a one way shipping.

    However they said that if the repair is going to be over $100, they are not going to fix it. Hence I would lose time + shipping.

    So instead I went via T-Mobile insurance which was $130 all together and they sent me a brand new Nexus 4.

  8. I have a broken, locked screen on my nexus 4. I have a ton of pictures of my new son on the phone that I really need to be able to retrieve. How can I do this with a locked, broken screen?

  9. Same thing happened to me too. Exactly 20 days after owning it as well. You said you paid T-Mobile insurance $130. Were you already paying them monthly for insurance before it broke and $130 was the deductible they had you pay?

    Thanks for your post on the factory reset with a busted screen!

  10. Plug a mouse into the tablet using a usb (female) to mini usb (male) adapter. You’ll be able to unlock the tablet and navigate as you usually can with your finger.

  11. @Chad: re-read the entire post. This is all about a nexus FOUR, not SEVEN. This is not a tablet, but a phone. And may I add that the Nexus 4 does not have USB OTG enabled, so you’re unable to use a mouse/keyboard on it (unless you have an Y USB adapter and do some stuff on the phone, like rooting and something else I don’t remember now).

  12. I too just bought this nexus 4 and the back glass broke from simple heat transference. Cold Granite, Warm Glass. I contacted LG and was told they would require me to send in the phone for a repair at my cost as it is not a functional defect and that it was due to dropping the phone.
    I told them no and that I would repair the phone myself. They stated I would void the warranty if I did so. I responded stating that there was no warranty as it contains a design flaw and that LG themselves redesigned the back cover to protect the glass backing. Their new cover has tiny feet which prevent the glass from touching a surface. They denied this and hung up on me.
    While this phone functions properly it does suffer from an engineering defect which LG Electronics has redesigned on Google’s say so, they refuse to admit it. Thumbs down for LG as a company that stands behind its product.
    I have since ordered a new back at a cost of 79.00 USD and will install it myself.

  13. you are very skilled in problem soving, i would have likely just cried like a wee child….similar to my current behavior.
    hoping you can help me out, pretty please??
    im trying to root my Nexus 4, but need to create a backup first. the issue is that im told “adb: unable to connect to backup” when i type adb backup -all into my command prompt. my search through forums and such has been fruitless. your post above leads me to believe your familiar with adb and are quite intelligent, possessing the skills necessary to find a solution to my problem. now if your generous enough to take the time to help out a stranger id be muy mucho appreciative.

    i have the app, titanium backup, i have used to backup my settings and apps. is this sufficient to restore my phone back to its previous state. im unsure it has stored all my data and such to fully restore my phone….clearly the task of rooting my phone is above my knowledge/skill level and will likely lose all everything, if not brick the phone, but your assistance will not be in vein i promise………….hope you made it thru all that and are still willing to help :/ soon to be forever in your debt, i hope

  14. @Jim,

    There are a couple of reasons why “adb” would not be able to connect:

      * adb debugging needs to be enabled
      * device (your phone) can not be discovered
      * "backup" is not supported with the Android you have installed 
        (this last one is unlikely the reason with Nexus 4)

    While “adb backup” sounds logical, an “adb pull” is usually used to back things up. I also used it in the article above.

    Here is some help on backing up using “adb pull”

    Here is a very useful discussion of possible reasons and ways to do it.


  15. Thanks for sharing your story. Would you possibly have any advice for my situation?

    I have a Samsung Galaxy Tab 7 Plus (Honeycomb) and it got stuck in recovery mode, and none of the solutions I searched up and down for worked. There was one thing left to try based on a suggestion of a similar situation: Take out the battery and reseat it, after following careful instructions on removing the cover and doing so.

    I failed and cracked the glass, with a tiny bit of circuit board exposed. Is there any risk to attempting to charge it and seeing if it will be recognized via USB cable to at least back up my stuff? It’s probably not worth the repair cost and who knows if they’d be able to get it out of recovery mode since the usual solutions failed.

    Thanks for reading..


  16. @Will,

    It seems that attempting charging your Galaxy Tab would be the only choice, in case you are not going to send it for repairs. It is risky, but it may at least bring its data back.


  17. I’m really trying to understand the business of stripping down sdcard from a Samsung Galaxy S3 that my gf’s sister was enough of a klotz to break its screen. However, I don’t understand this root business and I don’t get to succeed doing anything on my Mac. Ifyou’d be happy to walk me through it I don’t ind paying you for the trouble. If that’s something you’d consider?

    very best of regards,

  18. @Steph,

    This is not something I usually do, but you can find people who can walk you through, share links/instructions with you, and most likely with no charge at


  19. is it safe to say that the data recovery procedure described above will not work for people that didn’t have the USB Debugging enabled before their Nexus 4 screen became broken?


  20. Unfortunately, I’ve got into a same problem. And the article is good.

    But it looks like it’s not useful anymore. With the last Android versions, being connected it simply doesn’t see device attached until the screen is unlocked.

    Neither abd can see it, nor Moborobo could be used…

  21. @Sergey,

    I Have the same issue. I think the same way, the last Android versions denny the access from adb. Could you solve the problem of adb connection ?


  22. Seems like I am little lucky one that my Nexus 4 survived 4 months.
    Then the obvious thing happened, slip of phone on hard surface just from 2 feet and BOOM!!!
    My Nexus 4 got badly cracked … worse than shown in the article.
    I am so disappointed with Google & LG … whom I considered to be genuine companies.
    How could they such a pathetic phone that couldn’t survive daily wear-n-tear!!!

    I was eagerly waiting for Nexus 5, but after the Nexus 4 blunder, I doubt that Google & LG will offer something solid…. What are your thoughts?

  23. is there any way to recover pictures and videos thru the fast boot method? My Nexus 4 fell and the screen broke. I tried to read the screen shots above hoping there would be a recovery option instead of just wiping the phone. I’m not tech-savvy enough to know what is meant to know what to do with instructions “./adb -d reboot recovery”. With a locked screen, is it possible to do it from my PC if I have it plugged into the phone?

  24. Hey,

    Thanks for the step by step on the Nexus 4 memory wipe. Was looking everywhere for something like it. Worked like a charm. Thanks again!

  25. This is great for people who have cracked the outer glass, but in my case the AMOLED cracked and the display is completely broken(i.e. – black screen).

  26. That is amazinnnngggggggg and very helpful.
    Thank youuu so muchhhhh …

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