You can now update your Samsung Galaxy S2 i9100 to Android 5.1based OmniROM custom firmware. OmniROM team is the first to roll out the Lollipop firmware for Galaxy S2. This custom firmwareis a very popular ROM featuring some amazing customization options and is built from AOSP sources. Here is how toupdate Galaxy S2 I9100 to Android 5.1 Lollipop based OmniROM.

Prerequisites to update Galaxy S2 I9100 to Android 5.1 Lollipop OmniROM:

Backup any important datafrom your Samsung Galaxy S2 as a complete wipe will be required during the flashing process.Enable USB debugging option on your device:Settings>DevelopmentOptions>USB debugging.Samsung Galaxy S2 must berooted, unlockedand installed with a recovery tool likeTWRPorCWM.Your device must be charged to at least 60% of power.

How toupdate Galaxy S2 I9100 to Android 5.1 OmniROM:

Required files: downloadthe OmniROM Android 5.1 Lollipopcustom firmware for Galaxy S2 i9100 fromhereand save it on your computer. Do not extract the contents. Also download the Google Apps Package for your SGS2 fromhere.

ConnectGalaxyS2 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 S2.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 OmniROMAndroid 5.1 custom firmware and confirm the flashing process.Once done, repeat the above step for installing GApps on your smartphone.After installation is done successfully, return back to main recovery menu and reboot your Samsung Galaxy S2 i9100 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 SGS2, boot intorecovery, selectbackup and restorethen restore your previous ROM by selecting it from the list.

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