With the release of Android KitKat 4.4 we have learned that Google is creating a new method to how Android apps run. Dalvik, the virtual machine that allows Android code to run on smartphones and tablets, is soon to be replaced by a new runtime engine called Android Runtime (ART).

Google said today that ART could replace Dalvik at the next possible opportunity, likely the next update to the Android operating system.

“I don't want to make promises but I imagine next release it could be ready. Maybe. We will switch over when it is ready. It is actually quite fast now and now we are just really optimizing it and assuming those optimizations go well I assume that we will be ready to switch over at the next opportunity,” said Android head engineer Dave Burke in an interview with ReadWrite. “We are working actively on it and we will port over on it when we think it is better than Dalvik in every way.”

Dalvik has been with Android from the very beginning of its life. Burke and Android engineers believe that it is getting fairly old. The Android team had not put a lot of active work into Dalvik to improve it other than optimizing it and making it portable for various evolutions of Android hardware.
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Android Runtime works now and is available as a developer setting in any device running Android 4.4 KitKat. Burke notes that most consumers would probably not notice the difference. I have had ART running on an Nexus 5 since this morning and have noticed that apps may be a bit snappier, but otherwise it hasn’t negatively effected the performance of apps or the device.
More at Read/Write...

--jeremy