Android is improved a lot in last few months. after pushing out Android 4.4 (KitKat) update, they at last leave behind the conventional way of dalvik VM to run apps and applied their new ART (Android runtime) . for instance this option is still in development but Google is thinking about making it default in it’s future versions of android.
So,I guess you guys are pretty much confused that what is all this about? let me explain.
WHAT IS DALVIK?
Dalvik is a previous version of android run-time which android system uses to run applications.but it can only run codes at the moment when it needed by “Just In time” or JIT compiler. which was compile classes of android apps when you opened them so at that time it will consume more RAM and Battery also you will feel noticeable lag on low end devices and some times also on high end devices.
WHAT IS ART?
ART on the other hand uses Ahead Of Time Compiler (AOT) which will compile user apps ahead of their needs so phone would be run smoothly and consume less RAM and reportedly it increases battery performance too. This will require more ROM on system because compiling apps before, they need to consume space but on the other hand you are going to have more battery, and improvement in speed. This will also increase the speed of scrolling and loading pictures and videos.
At this moment, ART can improve slight in battery life and performance but in future this figure will increase drastically. Currently not all apps are optimized by ART and is not having custom features like xposed framework and GravityBox, which can give your phone lots of tweaks. But they are not working with ART.so if you want to use them you have to keep Dalvik.
NOTE : Xposed framework & GravityBox are custom frameworks, with the help of which you will be able to put custom features and tweaks of custom firmwares. Root is required for it.
Currently, if your phone have android KitKat update (4.4.x) you can able to run your apps on ART (android run-time) by enabling it from “developers options”.
Let’s talk about some benchmarks now,
(courtesy :android police)
We can see that in animation run-down with updated images tests ART(android run time) wins. But as of now, everything is not optimized with ART so some of devices will not get better battery life and performance.
As example,Antutu Benchmark of Nexus 5.
You will be in a dilemma that why is Dalvik giving you more performance than ART. But as I told you before, ART is still in development stage and google may put ART default from it’s next version 4.5 or 5.0 whatever it is! So after that we will see drastic improvement in performance and battery life.
So, this was all about Dalvik and ART.
If you have any doubts regarding this article feel free to post it in comments !