Here is how toupdate Galaxy S3 T999 to Android 4.4.4 based C-ROM custom firmware. Based on AOSP sources, C-ROM is one of the few stable and smooth custom firmware available on KitKat. Enjoy the level of customization provided by this ROM.

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C-ROM Android 4.4.4 KitKat:

Moved Halo Icon back to on Statusbar ( Not sure if it works good on HDPI devices).Launch the msimsettingswhen the new card dialog appearsDisable keyguard widget frameDon’t hide baseband on dual sim devicesPort BatteryBarFrameworks: Fix linked volume does not persist after reboot.Change notification background from holo to kitkat greyFix possible ANR and navigation bar freezeFrameworks: do not kill favorite recent appsFrameworks: fix possible NPE + and missing expandable panel correctionFixed Recent Clear Butons colorsDon’t register methods when there’s nothingto register.Get rid of noise during boot.InCallUI: Fix potential NPELauncher3: Icon pack supportOmniSwitch: added icon pack support

Prerequisites to update Galaxy S3 T999 to Android 4.4.4 C-ROM custom ROM:

Backup any important datafrom your Samsung Galaxy S3 SGH-T999 as a complete wipe will be required during the flashing process.Enable USB debugging option on your device:Settings>DevelopmentOptions>USB debugging.Samsung Galaxy S3 T999 must berooted, unlocked and installed with a recovery tool likeTWRPorCWM.Your device must be charged to at least 60% of power.

Note:this tutorial is focused on T-Mobile Samsung Galaxy S3 SGH-T999; kindly do not try this guide on otherAndroid&Samsungdevices.

How to update Galaxy S3 T999 to Android 4.4.4 based C-ROM:

Required files: download C-ROMAndroid 4.4.4 KitKatcustom firmware for Galaxy S3 fromhereand save it on your computer. Do not extract the contents.

ConnectGalaxyS3 to your computer using a USB cable and copy the zip file to your phone’s SD card.Disconnect the USB cord andpower off yourGalaxy S3.Boot it into recovery mode bypressing and holdingVolume Up+Home+Powerbuttons together.Perform aNandroid backupof your current OS:Backup>backup and restoreon ClockworkMod recovery.Wipe data task: from CWM recovery menu, selectwipe data / factory resetand confirm the process. Then go on towipe cache partitionandwipe dalvik cache.From recovery menu, selectinstall zip from sdcardfollowed bychoose zip from sdcard.Locate the C-ROM Android 4.4.4 custom firmware and confirm the flashing process.Return back to main recovery menu and reboot your T-Mobile Samsung Galaxy S3 into the new custom ROM. First boot takes a good 5 minutes so please be patient.

How to restore:If you want to return to previous OS on your SGS3, boot intorecovery, selectbackup and restorethen restore your previous ROM by selecting it from the list.

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