Don't believe the bashing!
I don't know with what kind of mindset these people watched the movie (if they even watched it...somehow I doubt...or they didn't get any emotional connect).
I bet that negativity comes because of bias and not because of performances or content.
Or - maybe - it's my connect to what goes on/can go on in youngsters and between youngsters and parents.
In my eyes (and feeling), it was a fine ensemble performance where each got a possibility to shine...and shine they did - in their respective role... no unbelievable character portray.
I also liked the subject, the interpersonal changes (visible in the change of body language and behaviour)...and the friendship-theme.
So, now, after a prolonged second viewing, I'll read the reviews (from my side no comments about how they spoke Hindi...but the music was gorgeous...energetic, lovely, infectious 
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