CM12.1 On ZenFone 2: Closer to What Should Have Been

CM12.1 On ZenFone 2: Closer to What Should Have Been

All ZenFone 2 models offer some of the best bang-per-buck ratios available today, but this didn’t stretch past the hardware. ASUS’ ZenUI has enough going for it, but the general consensus is very clear. When I originally reviewed the ZenFone 2, I was one of those who complained about its nonsensical bloatware among other pointless decisions that kept the software down. ZenUI was no Stock Android, but now we have another solution.


CM12.1 was reported to come to the ZenFone 2, but you don’t have to wait too long to get a taste of it. The ZenFone 2 already has an unofficial version making rounds, and it gives us a glimpse of what’s coming for those who jumped into the purchase despite the phone’s stock software and development complications. I’ve been test driving a build of CM12.1 on the ZenFone 2 for a day, and I’ve come to some good conclusions. Mainly, that this is close to what the ZenFone 2 should have provided off-the-bat. Before jumpting into that, here you will find the resources you need to make it happen for your device:

The installation follows standard flashing procedure, and you can find out how to get there in our forums. It’s as straightforward as you would expect, and with the simplified tools provided, unlocking the phone and installing a custom recovery shouldn’t take you long:



Once you load up the ROM, make sure to install an x86-compatible GApps package if you want Google apps and services. This is one that worked for me, courtesy of XDA Senior Member deadman96385.

Disclaimer: This ROM is in development and an unofficial release as of yet, so some bugs are to be expected and encountered. The version I tried was not the one listed in the forums, but rather one provided yesterday at r/ZenFone2. This is not meant to be a review of CyanogenMod 12.1 nor this particular release, but rather initial impressions of the UX of an early AOSP-based ROM on the ZenFone 2.



Onto the ROM itself: on a first boot, I immediately realized just how much more vibrant the screen seemed. This is not just because of the base theme having a much more gracious color palette than ZenUI’s default, but also because the screen can seemingly get dimmer and brighter. The ZenFone 2’s ZenUI had a limit in maximum brightness, which could be upped through third party software. This ROM, however, seemingly allows for the maximum from the get go. Dynamic contrast and content adaptive backlighting (CABC) is also seemingly missing, as jumping from all-black to all-white screens does not produce a jarring change in brightness. The Material Design color palette compliments the ZenFone 2’s LCD display much better than the stock aesthetics of ZenUI do, and I believe this is a change you will notice on the first boot.


As for the UI, this is just what you would expect out of CyanogenMod 12.1. All its material goodness remains, and it runs like a dream on this hardware. The theme engine works as well, and given that the ZenUI theme engine was so lacking, this is good news for all customization lovers out there. For all its bloat, the ZenUI did a very good job in terms of performance. CyanogenMod 12.1 does not seem to be much faster per se (in terms of opening applications), but it does feel much more lightweight and responsive in most areas (except for the Trebuchet Launcher’s drawer, but that can be easily replaced). Firing applications is handled graciously without stutters nor slowdowns, and multitasking is as speedy as an Android device should handle it. Benchmarks do not show significant (or rather, abnormal) variations, but I haven’t done a serious round of testing yet. What matters the most is that the user experience is now more straightforward than ever.


The tested build had no bloat, which is a stark contrast to my first reaction to the ZenUI. I have been used to CyanogenMod ROMs for a while, but to see such a clean experience on this particular device is refreshing. The fact that this is running on x86 hardware seems to have no detriment to the actual user experience apart from the odd bug or incompatibility, which the stock ZenUI ROM had plenty of anyway. Something I noticed is that gaming performance seems to be a little worse than it was before, and 3D games like Asphalt showed stuttering I had not encountered on ZenUI. But remember, this is an early, unofficial build. This being said, I tried using Gamebench to confirm this by measuring frames-per-second on two separate occasions, but both ended up with a reboot. This leads me to the bugs:

What I tested is not a perfect ROM, and I’ve found many little issues with it. This was to be expected, however, given this is an early, unofficial release meant for beta testing. Among some issues, I’ve had the System UI crash on me entirely during a call, the default camera app crashing whenever I switch to the front camera, and a couple of inconsistencies in the status bar. The build posted in the forum link might not have as many issues, however. Despite this, I am enjoying the ROM because it brings the experience much closer to what many believe the ZenFone 2 should have originally offered. Performance is top notch, RAM management is as great as ever. However, while the stock ROM’s camera post-processing kept image quality down, the lack ASUS’s custom camera software seems to have dragged it down further. This was expected, as it’s something typical of AOSP-based ROMs on devices that come with OEM ROMs (such as Samsung devices).


A final note on battery life: a complaint I had with the ZenFone 2 on its stock ROM was inconsistent battery life. Given that I have only been test driving the early CM12.1 ROM for a day, I don’t have many samples to show and no conclusive statements to make. The overnight drain sample here should not be taken as an absolute, and while disappointing, we must remember this is an unofficial beta. I haven’t gotten around to measuring the temperature in serious testing yet, but the device does seem to be all-around warmer during regular usage.


Overall, this is much closer to what the ZenFone 2 should have been. Developing for this platform might not be as easy as it is for the more mainstream devices and the standard ARM processors, but despite this, in a short amount of time we’ve achieved a lot. It wasn’t long ago when a bootloader unlock method was found within our forums, and before we even had a review up, there already were ways to root the phone, install TWRP and have Xposed up and running as well. Running a CyanogenMod ROM in this device opens up a lot of possibilities. If you had been considering the ZenFone 2, this should be good news. If you have it, I strongly suggest you try this out, because it might just make you very excited for what’s to come.

We will keep you updated on any interesting findings and developments regarding the ZenFone 2’s new-found ROM scene.


Are you excited for these new developments for the ZenFone 2? Let us know!


Note: We seem to have some trouble with our image previews/thumbnails right now, please excuse the slight pixelation!

About author

Mario Tomás Serrafero
Mario Tomás Serrafero

Mario developed his love for technology in Argentina, where a flagship smartphone costs a few months of salary. Forced to maximize whatever device he could get, he came to know and love XDA. Quantifying smartphone metrics and creating benchmarks are his favorite hobbies. Mario holds a Bachelor's in Mathematics and currently spends most of his time classifying cat and dog pictures as a Data Science graduate student.