Kindly help me out.
The app I am working on (still on whiteboard, need expert opinion on this approach) will simply fetch news from different news sources and will display to its user.
If you are more getting to the bits and pieces and doing all on your own check Cordova which is the base of the two mentioned above.
So do I still have to rely on Java?
No for most of the cases.
Will there be any disadvantage(s) of not using Java?
Will I still be able to extend my app(s) in the future?
Yes but again depend on which framework you are doing it and what it allows.
Am I asking a really stupid question here?
Not at all.
If you think about avoiding Java, but not Dalvik altogether, you could use Kotlin.
Very neat language by JetBrains; thus it integrates well with Android Studio (or IntelliJ Idea). Much less verbose than Java, and introduces some functional programming concepts. Kind of like Scala, only simplier. It can coexist with Java in an Android project, or you can move everything to Kotlin. The IDE plugin allows for converting Java code into Kotlin automatically, so it's easy and facilitates learning it.
It's a niche language and not 100% mature yet. I wouldn't advocate using it in large scale commercial projects, but for something light-weight or a hobby app; go for it. As a learning experience, and for the taste of a slightly different paradigm.
What would you be missing on?
Kotlin skills are not sought after by employers (as of now at least), so learning it doesn't add significant experience to your CV. Although a project done in Kotlin could still make for an interesting entry on a resume, indicating an enthusiastic programmer;
Superb refactoring functionality provided by Android Studio for Java is very limited when coding in Kotlin.
It has its counterpart born in the Eclipse world: http://eclipse.org/xtend/ - which seems to be somewhat similar. I've never tried that one though.