OPPO has unveiled a mid-range device A57 in China with decent specs. OPPO, who recently launched two high end smartphones R9s and R9s Plus, has now unveiled a mid-range smartphone, to provide a tough time to its competitors. With its sensational front camera i.e. 13-megapixels and 3GB RAM along with 32GB ROM, it proves to be a decent offering by OPPO, despite its below par chipset.