To the uninitiated, the world of Android ROMs can be more than a little confusing. Since Android is based on Linux and therefore large portions of it are licensed under the GPL, enthusiasts are free to create and release their own builds.
That’s where some of the confusion comes from. When you buy an Android device, it comes with Android pre-loaded of course. Then, when Google releases a new version of Android, it releases it to the vendors and to the phone companies. If your device is really popular and you’re really lucky, you’ll get an update from either the carrier or the vendor. Usually the update comes with some ridealong software, which you may or may not find useful.
Enthusiast-built Android ROMs tend to come out much sooner than official ROMs sanctioned by the manufacturer, and they don’t come with the bloatware either, so they tend to run a lot better. My venerable Samsung Galaxy S4G phone, which is nearly three years old, runs better on an enthusiast-built ROM than it ever ran with the vendor-provided one, and the enthusiast-built ROMs are much more up to date.
Just as an example, Android 4.4 (also known as Kit Kat) was released on 31 October 2013–Kit Kats for Halloween, get it? Google uploaded the source code that night. Talk of experimental Android 4.4 builds commenced immediately, and within a day or two, a few developers had Kit Kat running to some degree on hardware that will probably never see an official build for them.
So, if you want more features, want more control over your device, or just want to stay more up to date, an aftermarket, enthusiast-produced Android ROM is the way to go.
The biggest, most widely supported, and most popular unofficial Android ROM is Cyanogenmod, by a large margin. Many people’s experience with aftermarket Android ROMs begins and ends with Cyanogenmod. And there are two things you can pretty much take for granted with it: It’s very likely that Cyanogenmod is available for your device, and it’s a safe bet that it’s faster and more configurable than whatever came with your device.
But Cyanogenmod isn’t the only game in town. In some cases, something designed from the ground up for a particular device might run a little faster than Cyanogenmod does. Or the development team might just have a different focus on it. I’m personally fond of Slim ROMs. As the name suggests, they tend to be minimalistic, but that’s usually what I want. I like having the basics, which leaves more room for the apps I need for what I do. There are several places to find ROMs, but my favorite place by far is XDA Developers, where you’ll find ROMs and instructions.
Installation varies a bit from device to device, but, basically, it starts with rooting, then installing a custom bootloader. Think of the bootloader like the Windows boot menu, or Linux LILO or GRUB. Then you download your ROM in the form of a zip file, plus a Google apps bundle (Google doesn’t permit the two to be bundled together), write those to an SD card, insert the SD card, boot the device, select recovery, and install the zip files you need.
If the device doesn’t have an SD card slot, the process usually involves connecting the device to a computer via USB, issuing a key sequence to put it into download mode, then using a program to write the ROM to the device.
My immediate family owns a total of four Android devices between us. Two are still stock. One will get an aftermarket ROM loaded on it just as soon as I get around to backing up all of the data and loading a new ROM on it. The other doesn’t have a fully functional aftermarket ROM available yet–the best ROM available doesn’t support the camera or NFC yet. I don’t care about NFC, but since I do occasionally use the camera, I want that.
I look at it like I look at a PC running Windows. The overwhelming majority of people who buy PCs are content just to use them the way the vendor loaded and configured them, maybe loading a few more programs on it, but leaving Windows alone except–hopefully–to let it auto-update. Then there’s me and people like me: When we have to buy a ready-made PC, we immediately unbox it, format the hard drive, and install Windows ourselves, then load what we want on it. The computer works better that way.
If you’re the type who reformats and reinstalls Windows as soon as you get the PC out of the box, or if you’re the type who builds PCs from parts and then loads Windows on it yourself, you’re probably going to like Android a lot better when you loaded it yourself too. Which means diving into the world of ROMs.