If you have an Android phone or tablet, it's easy to install a custom operating system that's more appropriate for your needs than the stock Android OS. However, while rooting your Android phone is simple, selecting the right custom ROM can be challenging.
To help you make the right decision, I compiled a list of the best ROMs we've seen for devices running either Ice Cream Sandwich (Android 4.0) or Gingerbread (Android 2.3). If your Android device is still running Froyo (Android 2.2), the Gingerbread and Ice Cream Sandwich ROMs will probably work, but I recommend taking a hard look first; all of these custom ROM projects are maintained by independent Android enthusiasts, so install them at your own risk.
Editor's note: We tested these ROMs using a Samsung Nexus S. Android ROMs behave differently depending on which phone model you have, so be sure to research a ROM thoroughly before installing it onto your device.
Ice Cream Sandwich ROM Roundup
Generally I prefer a ROM that’s as close to vanilla Android as I can get, so plain old Codename Android was an obvious choice. It's the first ROM that I tested. Thankfully this open-source ROM has everything necessary to replace the stock Android OS in daily use. Here’s how Codename Android performed when I put it through its paces.
Reliability: This can be an issue for a lot of ROMs, with force-close errors being as annoying as Windows' infamous Blue Screen of Death. Thankfully, Codename Android is as reliable as ROMs come. As a test, I installed the Angry Birds and Google Currents apps and made extensive use of them, as well as noting whether any apps crashed. I found Codename Android to be extremely reliable: Apps didn’t crash, and the ROM itself remained rock-solid stable. My phone did boot up a tad slower running Codename Android than it did running stock Ice Cream Sandwich, but that isn't really a concern. The camera in particular was more snappy than stock when opening from the lock screen.
Speed: I don't have a lot to say here. Codename Android felt like one of the fastest ROMs I played with during my testing. It's designed to be a speedy ROM, and the developers delivered on that promise. Even after I turned on all the extra screens (seven in total) and customized nearly every facet of the ROM, using my phone felt gloriously fast.
Installation: Installing Codename Android is as easy as downloading the appropriate ROM for your device, rooting/unlocking your device, and installing the .zip file from recovery mode. Installing the Franco kernel adds some annoyance to that process, but it’s just another file to install from recovery--hardly a dealbreaker. In my tests, the initial boot after install took a couple extra minutes--and I always sweat that time, fearing I did something wrong--but it installed without any hitches.
General feel: Codename Android feels like stock Android, with some additional cool things stuffed into it. You'll find none of the carrier bloat, of course, and you won’t see anything like the cumbersome HTC Sense overlay here. It’s a pure, unadulterated Google experience, and it’s awesome.
Battery life: The developer claims that Codename Android improves your device's battery life, and with the addition of the Franco kernel I did see an impressive gain over stock Android. I easily could get 12-plus hours of moderate usage from my Galaxy Nexus, which is a good 1 to 2 hours more than I could eke out on stock Android. I didn’t expect to see that much of a difference, honestly. Note: I do not have 4G in my area, so I did this testing with the 4G antenna turned off.
Final thoughts: Codename Android is one of the best ROMs I’ve used for ICS. If you want something that looks and feels like ICS but has a ton of additional swagger, get Codename Android.
If you don’t like how stock Android looks, try ViciousMIUI. It's hugely popular in China, and though I find MIUI a little too much like iOS for my taste, its popularity both abroad and here in the United States is undeniable.
Reliability: MIUI is designed to be stable, and it is. Currently it has a bug with YouTube occasionally crashing, but MIUI is a new ROM for ICS, so you just have to roll with the punches. While using MIUI, I encountered no issues testing standard functions on my phone, and I saw no slowdowns or crashing during extensive use of Angry Birds or Google Currents. For a beta ROM, Vicious MIUI is relatively solid.
Speed: As a ROM built for daily driver stability, MIUI is no screamer. It runs about as fast as standard ICS on the Galaxy Nexus, which is as fast as anyone could want. No surprises here, as MIUI isn’t made to run benchmarks. It does what it needs to do as efficiently as possible, and it succeeds.
Installation: MIUI installed easily via the standard recovery mode, and it needed no custom kernels to be installed to maximize performance. I really enjoy how easy it is to install these ROMs.
General feel: As far as ROMs go, MIUI is not my favorite one to use. I didn't like the lack of an application drawer; being able to put your applications into folders (just as in iOS) is mainstream now, but I wish MIUI included an option to turn on the standard Android app drawer. Let's hope that, as it evolves on ICS, we’ll see MIUI shift away from the iOS aesthetic.
Battery life: My battery performance running MIUI was completely standard; it didn’t perform any differently than stock Android. I could pull about 10 hours of moderate usage in a 3G environment. Still, it's good to see ROMs that don’t drain your phone battery dry in a handful of hours.
Final thoughts: Not a ROM for me, but if you’re sick of stock Android or if you just want to try something different but stable, give ViciousMIUI a try. You won’t be disappointed.
AOSP Bugless Beast
Here's another open-source ROM that was a delight to test out. AOSP Bugless Beast is very similar to stock Android, and doesn’t have a lot of bells and whistles. Note that NFC didn’t work under Bugless Beast at the time of my testing (but I would have been unable to test it anyway, because nobody near me actually uses NFC yet).
Reliability: Bugless Beast never crashed. This ROM ran Angry Birds and Currents like a champ every time, and my normal usage never produced a force-close. So far, totally glitch-free.
Speed: Since Bugless Beast is a no-frills ROM, you're probably expecting it to be snappy--and you’re right. This ROM rivals Codename Android in sheer speed. Everything was fast, and I saw no latency anywhere. I loved the speed, and running widgets galore on multiple screens never slowed anything down.
Installation: No issues. Bugless Beast is simple to install, and I had no trouble getting it up and running.
General feel: Bugless Beast is a pretty vanilla ICS port, so it feels like a streamlined Android. It imposes very little slowdown, and navigating the Android interface is nice and smooth. The Gingerbread (2.3) version of Bugless Beast is extremely popular for the same reasons.
Battery life: The battery performance on Bugless Beast was fairly surprising. I was able to pull over 10 hours with moderate usage, which is a minor improvement over the stock Android ICS ROM. Bugless Beast didn't quite match the battery-sipping performance of Codename Android, but it's still impressive.
Final thoughts: Bugless Beast is a great ROM. If you don’t want to mess with custom kernels, and you need something fast and stable with good battery life, give it a shot.
Next page: Gingerbread ROMs