Monday, February 13, 2012

Part 3 : Flashing a Custom ROM on the Galaxy Nexus

This is Part 3 of a series of posts on how to flash a Custom ROM on the Galaxy Nexus. Part 1 dealt with rooting the phone and Part 2 dealt with preparing to load a Custom ROM. I think Part 2 and 3 would be applicable for most Android devices, but since I don't have experience with them, I would say that this guide works for the Galaxy Nexus.

Start the process by making sure your phone is adequately charged.

1) Load the Custom ROM on your phone
This was where Part 2 left off. I am assuming that you have downloaded two zip files - a ROM and a Gapps file as mentioned by the developer and then checked the MD5 sums (refer to the previous post). Connect your phone to your PC and transfer the two zip files from your PC to the internal SD Card of the Nexus. To access  them easily, do not put them into a folder. Leave them in the root so you can find them easily. And make sure they are not unzipped.

2) Disconnect the phone from the PC

3) Fire up ROM Manager and select Boot into Recovery from the menu

4) Follow the instructions of the developer
They usually go like this
Make a nandroid backup (I am assuming you have already done this if you read my previous post. Also, you should have downloaded Titanium Backup and backed up your apps)
Select Factory Reset/ Wipe Data
Select Wipe Cache Partition
Select file from SD Card - here you can access and select the ZIP files you have loaded. First flash the ROM and then the Gapps file.
Reboot

4) Your ROM will load. The first time you flash a ROM, it will take a long time to load, so don't panic!

You will see the language selection screen, select the language of your choice

You will be prompted to set up wi-fi, do this if you wish.

When the ROM starts, Google will prompt you to sign in. Do this. It will also ask you if it should restore your backups. Make sure you do not check this option.

Now you will see a blank home screen minus your apps. Do not panic!

Through the menu button, access the app drawer and see whether Titanium Backup has been installed. If not, go to the Android market and download 1) Titanium Backup Free 2) Titanium Backup Pro (if you have purchased a license key). You must download both separately, in this order.

Now fire up the app and go to the backup/ restore menu and select the 'batch'option


Scroll down to see the backup options. What I usually do is restore all apps with data first. Then I selectively go to system apps and restore data like call logs, SMS etc. I do not restore apps+system data because it can cause a crash if the ROM is incompatible with earlier system data. If you restore any system data, Titanium Backup will ask you to reboot your phone - do this to avoid problems.

If you have purchased Titanium Pro, it will process the batch command in one shot. If you have the free version, you have to approve and install each app individually.


After you have performed these steps, you will see all your apps back in the app drawer. You probably still need to populate your home screen with apps if the launcher has changed.

Now you can explore the features of your new ROM, and enjoy it! Remember to make another Nandroid backup if you like the ROM and plan to keep it. If you don't want to keep the ROM, or encounter bugs, make a Titanium Backup again. Then open ROM Manager and boot into recovery, and restore your earlier ROM through the 'restore' option. A saved ROM will automatically reload your home screen and apps, as they were earlier. You can restore any missing stuff through Titanium Backup.

If you like the ROM and plan to keep it, remember to make a donation to the developer through the forum where you downloaded the ROM. And do thank the team for the hard work they put in!