I don't think teens would buy into that design, especially girls. It is the best camera phone and also has a decent music player, but it's bulky. Another reason 720 wins over here is because it runs smoothly unlike the Android variants in this budget; they are laggy as hell.if she is not into apps what abt nokia 808. simple easy symbian, nice camera, lil over budget
My sister has the 720 and adores it very much compared to her previous Android phone. She hardly plays any games on her device and uses it mostly to browse, call and message. She finds the interface a lot better compared to Android, and she was really taken aback the first time she felt the smoothness of the UI. Every budget Android phone has a considerable lag. You'll hate to go back to it once you're on WP8 or even a high end Android device. Music and Camera is also the features she needs and there the Lumia 720 is the best offering in the <15k budget range.My younger sis has a Lumia 620. She had an el cheapo Dell XCD35 earlier but she hates her Lumia now. She finds the app support a big joke and while she hardly uses any apps the sheer lack of good games puts her off Windows 8. A few months of usage hasn't warmed her up to Windows Phone either.
So your best bet would be an Android device. At 15k you should get a dual core Android device which would have barely any lag.