AT&T Galaxy S4 ships with a locked bootloader, CyanogenMod founder reveals

by: Chris SmithApril 30, 2013

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An U.S. Galaxy S4 variant has been found to ship with a locked bootloader, potentially making the lives of developers and/or Android fans that love to customize their Android devices by running different ROMs all the more difficult.

The news comes from CyanogenMod founder Steve Kondik who took to Google+ to reveal his surprise at finding that the AT&T Galaxy S4 comes with a locked bootloader. Kondik went on to reveal that “MILLIONS [sic] of people run custom firmware” according to “STATS [sic]” and recommended users to stay away from AT&T’s Galaxy S4 version, especially developers and those buyers that want to run CyanogenMod or any other custom ROM on their new handset.

You can check his Google+ post in its entirety below:

Yep, it’s confirmed. The AT&T S4 authenticates the recovery and boot images before executing them.

I can’t see what AT&T has to possibly gain from this. GSM and LTE aren’t magical, tethering is controllable on the server side, and theft-of-services is not possible from the application processor side (or even from the modem side as far as I know). The same device is available on every carrier, so it’s not an exclusivity issue either. The modem processor has always been locked, and the casual user doesn’t want to mess with that part anyway. Samsung has always been developer-friendly, so I am guessing their hand was forced.

The only outcome I see here is stacks of bricked devices being sent back for warranty replacement due to the ease of causing a permanent boot failure, especially since the device is trivially rootable.

The arms race continues. News flash: MILLIONS of people run custom firmware (and I have the STATS to prove it). This is just a stupid move that will cost you customers and money.

I would not recommend buying this device on AT&T if you want to run CyanogenMod or another custom ROM, or if you are a developer and need to work with or debug the lower layers.

Are you going to ignore Galaxy S4 versions that will pack a locked bootloader (Verizon’s upcoming version is also believed to offer the same “feature”)? Or will you use the device as-is, without going for custom ROMs?

  • Ed

    The first related post above states a bootloader locked Sony Xperia Z can now be rooted. Doesn’t that imply the possibility an exploit could be found for the S4?

    • technology

      Locked bootloader can be rooted without unlocking the bootloader, The only problem with locked bootloader is that you can’t change kernel or flash a custom ROM.

      • Arsenal™

        well that suckz!

      • whoknowswhereor

        You want to stick with stock anyway. I tried pa and the gang on my note 2, stock is the smoothest, has the least bugs and most features. I still don’t agree that it is locked. Damn att.

        • technology

          Custom kernels helps with lags and battery issues.

      • kumar

        does t mobile also comes with locked bootloader?????????

    • CyanogenMod founder suggests dont even try ,and so don’t even try to listen to these other Root quackes on here

    • Andrew Dodd

      There’s a massive difference between root and being able to boot an unsigned kernel. People don’t seem to realize that rooting is not a big deal and only a tiny part of the equation on a locked down device.

      Rooting = easy
      Unofficial bootloader Unlock = hard

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  • John Mortimer

    Ha uh in the UK they sending them out sim free from networks

  • raindog469

    I’m not on AT&T, but I won’t buy a device with a locked bootloader from any carrier. Maybe I’ll switch out the ROM and maybe I won’t, but I want the option. Out of four Android devices in our house, we’ve changed ROMs on two, while the other two are rooted stock.

    Granted, we’re in that supposedly tiny minority who like to actually own the devices we pay for.

  • tawkon ( did some very interesting research on this phone, and came up with some specs that aren’t covered in this article… very interesting stuff

  • To Root or not to Root. there’s a reason for locking the phone, the company owns the phone until the end of your contract, that’s how the US market subsidizes the phone for $200 or less. The whole piece is mute, if one is into rooting you buy an unlocked phone and get your own sim card, and choose your network, as is done in all other non US markets. What is needed is the public to cry foul to US carriers who rip off customers will stupid coverage gimmicks, while the same phone and better coverage cost a 1/3 in Europe as it does in the US. Rooted phone or no the US cost is absurd and needs to go to single stream towers.