ART: The Android runtime that will eventually replace Dalvik is in KitKat in preview form

BY Stefan Constantinescu

Published 7 Nov 2013

Google has, for all intents and purposes, rewritten Android several times since first launching the platform back in 2008. But there’s a part of Android, the “engine”, better known as a runtime in programming terms, that’s stayed the same. You and I know it as Dalvik. Dalvik has gotten Google in a lot of trouble since it’s a fork of Java, which is owned by Oracle, and Oracle wants a cut of every Android device sold. According to Android Police, Google will eventually replace Dalvik with ART.

So what is ART?

Before I answer that, let me explain how Dalvik works. When you download an Android application, you’re downloading a program’s source code. That’s not 100% accurate, but bear with me because this is semi-complicated. Every time you then run the app you’ve downloaded, it assembles itself to run on your device. This is called “just in time compiling”.

ART takes a different approach. When you download an application, and it installs, when the installation process takes place the app fully compiles and then gets stores on your device. The brainiacs at Android Police say this results in applications ballooning in size by between 10% to 20%.

What pros does ART bring? Supposedly application start times are slashed, and because the app is compiled to be “native” upon installation, it should also run faster. Now ART is a part of Android 4.4 Jelly Bean, but it’s there only in preview form so developers can tinker with it. Eventually ART will replace Dalvik, but no one really knows when.

Expect to hear more about ART as time goes on. It’s important, but not right now.