Found this nice blog in Android weekly newsletter
Recentaly Android L had been in news a lot. There are many posts on net which describes the features coming in. The one which I like the most is android runtime or ART. Originally android uses dalvik runtime which converts the instructions at the time of running the app which had been a major reason of android being slow. In ART app code gets converted into executable ones and for ever. After that there is no conversion of code while running the app. This results in approximately 30% faster execution, hence a fast device and memory saving too. What few people know is that this feature is present in current kitkat version also. Only that its not the default setting. Goto settings, developer options, default runtime; and select ART and reboot the device.
It will take a while in upgrading apps. After that you will notice a faster device. Please keep in mind that at present some apps might not work properly. If that's a major issue you will need to revert back to dalvik runtime. At present I only had issue with one app which I can live with. Please also note that if you are not running kitkat you may have more issues or won't have the option of ART which depends on the version of Android you are running.
a nice intro of ART
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