When Android 4.4 ‘KitKat’ launched on October 31 something very important and underreported was introduced. Its name is ‘ART’ and with the Android 4.4.2 update released in early December it is ready for the mainstream. What is ART? Something that will, quite literally, change how all Android phones operate.
ART stands for ‘Android RunTime’ and its job couldn’t be more important: it runs the apps on Android devices. ART replaces ‘Dalvik’ (named after the Icelandic village where creator Dan Bornstein’s ancestors lived) which has performed this task since Android first appeared. As you might expect Dalvik was getting very long in the tooth and it wasn’t that great in the first place. In giving it the boot users will get two significant benefits:
1. More Speed
Why this happens requires a bit of tech speak.
Dalvik uses the ‘Just-in-time’ (JIT) process which means it has to transform app source code into an executable program every time it starts. That’s right, Android apps have to run through a conversion each time they are started.
By contrast ART uses the ‘Ahead-of-time’ (AOT) process and this compiles (aka does the conversion) when an app is installed. Using this method apps can launch up to twice as quickly which will have a dramatic effect on the sense of speed of your phone.
2. Better battery Life
A nifty-knock on effect of AOT processing is making app-launch a less intensive process, so your phone doesn’t have to work as hard which increases battery life. Using your phone you won’t see a major difference, but significant gains will come in standby as apps which run in the background will now do so more efficiently.
Early developer reports claim to see as much as a 30% boost in idle standby time, but there are so many variables here it is hard to measure. From my own experience with ART on a Nexus 5 I’d put it closer to 20%, which is not to be sniffed at given it will be updated and refined continuously.
Unfortunately switching to ART also has a couple of negatives.
1. It uses more storage
Or to be more precise: your installed apps will use more storage – roughly 10% to 20%. This is because the pre-compiled apps which allow ART to run so quickly and efficiently have to be installed this way which makes them bigger compared to Dalvik’s on-demand method. For those with a lot of apps installed this could take a significant chunk of your available space, they will also take a little longer to install.
2. Some apps are incompatible
Android 4.4.2 fixed a number of incompatibility issues (including some with mega apps such as WhatsApp) such that 99% are now compatible with ART. MX Player is the only significant app I’ve found to be incompatible (update: now fully compatible). A full list of apps compatible with ART can be found here. I’ve yet to find any significant apps that don’t work with ART on 4.4.2. If you do find a key app that doesn’t work it is possible to switch back to Dalvik on the settings menu shown here.
How do I get it?
For starters you will have to be running Android 4.4 which at this moment limits you to GoogleGOOG+0.05%’s Nexus series or a custom ROM on a rooted device. That should change quickly though as most major handset makers have now pledged to upgrade their main handsets to v4.4 in Q1. Since KitKat is also more friendly to budget phones than previous versions of Android it should be the Android version of choice for new budget phones as well.
ART is yet to become the default setting in Android 4.4.x so here is how you enable it:
1. Go to settings then ‘About Phone’
2. Tap the ‘Build Number’ repeatedly until you get the announcement you’re a developer
3. Go back to settings where you will see a new ‘Developer options’ section
4. In Developer options change ‘Select runtime’ to ‘Use ART’
Your phone will reboot and it will take 10 to 20 minutes to convert your existing app installations to be ART compatible. You’ll see a progress count during this. Don’t worry, all your app data is safe. Should you wish to switch back just choose ‘Use Dalvik’ in Developer options. The process takes about 10 minutes to complete and again no app data will be lost.
For those who do stick with ART pat yourself on the back. You’ve joined an exclusive club: those enjoying the future of Android.