If the Cityscape is only a Dream...: Installing Custom Android ROMs

My previous post discussed why and how to root your android phone.

An even older post looked at a test run of Android Ice Cream Sandwich

Do you want a more feature-rich, customisable, faster, better Android? Read on...

Android phones are designed so that the Android system resides on what is called Read Only Memory (ROM), however once you have rooted your phone, (links to instructions can be found at the top of the article), you now have permission to overwrite the ROM on your phone. You will have to check online to see what ROM images are available for particular make and model of phone. There are hundreds of different ROM's floating around the Internet providing many different features.

I have an 18 month old HTC desire and recently found an Android 4.0 ROM for it, with a few features cut back, which made my phone a lot faster and aesthetic, so I put that on just to give it a quick test run. But alas it is not stable and until it is, I am going to go for perhaps the most recommended and best supported custom ROM available, Cyanogenmod.

As always, take precaution and back up your data. Upgrading the the ROM on your device will void your warranty and may cause hardware issues. Please research your specific make and model carefully to see if anyone else has had problems rooting and installing a ROM, as I cannot be held liable should anything go wrong.

1. Research and get your ROM

The very first thing I would suggest you do is to research a little about your device, see how well it is supported and if anyone has run into any issues whilst upgrading it. Cyanogenmod supports a huge number of phones and has an excellent wiki and forum.

Next your phone needs to be rooted, so go and make sure you do that. A great resource for researching phone and ROM issues is the XDA developers forum.

Go to the homepage for your ROM of choice and download the .zip file for the ROM for your phone and read any instructions/warnings provided.

2. Install ROM Manager

You will need to install ROM Manager from the android market, this is an app that lets you make backups of your ROM image and install new ROMs. Once installed, you will want to select the option to ‘Flash ClockworkMod Recovery’ - this is a lifesaver if the ROM does not install properly as it provides an interface to install ROMs and so on, before booting into the ROM (for my phone, I power down the phone and power back up whilst holding the volume-down button to access the hidden console, it should be the same for you but may vary depending on make and model). Google up on Clockworkmod recovery should you need to use it (hopefully you wont).

3. Backup

Backup!

At this point, and I cannot emphasise this enough, you need to backup your personal data - Flashing a ROM on your phone wipes out everything! Photo’s, videos, music, notes, contacts and any other files you put on your phone. This was quite easy for me, since most of my data (calendar/docs/contacts) is synced automatically to my google account and my multimedia synced with my dropbox. No cables needed :)

It is also a good idea to backup a snapshot of your phones state (called a Nand backup) from within ROM manager; select ‘Backup Current ROM’ - this will make a byte for byte copy of your current ROM image from which you can restore your phone should things not go to plan. You will at this point want to connect your phone to your computer via USB cable and copy that backup folder to somewhere safe on your computer.

4. Install the new ROM

I wont cover formatting your SD card here, as Cyanogenmod doesn't require any complex partitioning to install, even for its apps2sd feature - but should you decide to install another ROM that does, use the ROM Managers partitioning feature - this will erase all data on the SD card.

With your phone connected to your computer, copy the ROM zip file to the top level folder on your SD card. Finally using the ROM Manager, select ‘install ROM from SD card’ and choose your ROM, and let it do its thing. This may take a few minutes and then the first boot will take a few more minutes - but the wait will be worth it.