Why does every Android phone have a different ROM?

Akhil K September 22, 2013

Why isn’t there a ROM which will work on any Android phone. My phone has Ice Cream Sandwich (ICS) with phone company added applications. So it is tweaked just a little bit.

But why can’t I install vanilla Android ICS, as it’s an open source operating system?

  1. Dalsan M
    September 23, 2013 at 7:53 am

    Each major brand of phones want their own customized version of android, with distinct "branded" apps and boot screens, etc. Cellphone providers want their own customizations and apps, as well as locking the phone to their service.

    Add in the mix of generic brands of phone manufacturers with many different hardware parts (CPU, GPU, wireless adapter, radio chipsets for cell phone signal, GPS, etc.), there would be too many drivers, kernels, and other things to even try to have a "one size fits all" type of operating system available for any and all phones. This is why there are developers, such as at XDA-Developers, create "vanilla" android versions for many popular phones. Also, newer versions of android need higher spec'd devices in order to run better and properly. Then, there are tablets and other devices to account for (screen size and resolution does matter). Instead of requiring 1GB ROM space, it would probably have to take much more than 4GB of space, something that would not be good for anyone (manufacturers, phone companies, and consumers). More storage space would be required to be built into phones, more work for the developers would be necessary, and ultimately the cost would be much higher because of this. Otherwise, software, hardware, and driver conflicts would occur.

    If you want to try another ROM for your phone, check out this thread: http://forum.xda-developers.com/showthread.php?t=2035941. Rooting the phone and installing a custom recovery would be necessary, but leave it to the developers at XDA to come through with a better or cleaner Android for many devices.

  2. Hovsep A
    September 23, 2013 at 7:43 am

    if a hardware do not support the universal ROM then a specific ROM is required to have fully operating system.

  3. Jan F
    September 22, 2013 at 9:21 pm

    The basic reasons there isn't 'a single ROM to work on all' are:
    (1) One ROM to work on multiple devices would require a lot of kernel drivers and modules. This would make the OS slow.
    (2) Having drivers, modules, libraries and other low-level code for multiple device would require a lot of file space.
    (3) Duo to Android being open source, manufacturers and providers can and want to add their own 'touch', applications, settings, optimizations.

    It's not that different from other mobile operating systems actually.

    For example Apples iOS is also device and generation specific. You will not be able to use the iPhone 4S firmware file for an iPhone 4, instead you will have to download another ~1GB large file. And this is an example where both, the hardware and software come from the same manufacturer/developer.