Its very hard to say which one is better because both are perfect as compared to their prices.I would say that Noir A900 is good for gaming because of its GPU, while Noir A20 is good for an normal user. –
See more at: http://www.incpak.com/tech/qmobile-noir-a900-vs-noir-a20-compairson/#sthash.8Tfx5BeW.dpuf
Faree's Weblog 