● Recommended ROMs And Installation
  • Carbon ROM
    This is an unofficial Jelly Bean port. It is based on the CyanogenMod ROM, with many, many more feature enhancements, yet it is stable and fast.
    However in my personal experience, I've found that it slows down over time. It might have been due to the fact that either it suffered from partition fragmentation, as it lives inside a file image located on the internal SD card FAT partition, or that I've just loaded my Droid 4 with far too many Apps and services that it could cope with. Therefore your millage may vary.

    • Installing it is easy (and I will assume that you've already install TWRP using SafeStrap)
    • Download the ROM from here or and copy it on the internal SD card (SDCard 0)
    • If you live outside the US and/or plan to use a GSM network, download the GSM patch from here and here and copy it on the internal SD card (SDCard 0)
    • Download the Gapps (google Apps) from here and copy it on the internal SD card (SDCard 0)
    • Either reboot in recovery from the stock ROM. Or power off your phone and boot into recovery by simultaneously press the vol up and down button and then power the power button, then scroll down with the vol down button to "BP Tools" and press the vol up button to reboot into into recovery.
    •  Click on the "Boot Opions" button
    • Click on "ROM-Slot-1" you can't install this Carbon ROM in any other slot, and create a ROM slot (you may want to increase the Cache partition to at least 100 MB)
    • Go back and click on the "Install" button and select the ROM zip file and flash it. Then proceed in the same manner to install the GSM patch and the Gapps (though if you want to 1st check and test this ROM before you commit to it, you may reboot straight into system and flash those at a later point).
    • Once you've successfully flashed the ROM, you can reboot the phone into "System" to use it with and configure the Carbon ROM.
    • Finally once you've committed to this ROM (or any other ROM this phone), DO make sure that you re-install the SafeStrap App as a backup to let you re-install TWRP and manage the different ROMs on your phone. This is because SafeStrap/TWRP is installed on the internal SD card (as a workaround of not being able to be flashed on the phone as it's bootloader is locked) and as it could be accidentally removed, you wouldn't be able to go back into TWRP unless you re-installed it.