How to develop a native mobile applications for android using dart language ? Is it possible?
Yes this is possible. A Dart application can be compiled to a regular JS/HTML app and packaged as such.
For a real world example see Veterninary Anesthesia in the Play store.This app was written in Dart and an installable phone application version was build with PhoneGap. The developer's blog extensively details how it was done.
Native Dart apps may come eventually. There's some reports of people compiling the Dart VM on Android. Currently, the Dart team are focussing on the Web client.