After a really long wait, Sony has officially commenced selling the Xperia Z1 f in Japan. Exclusive to NTT DoCoMo, the Xperia Z1 f is a 'Mini' version of the company's flagship Xperia Z1. In fact, it is powered by the same Snapdragon 800 quad-core chipset and 20 MP rear camera module. The only downgrade is the display, a 4.3-inch HD (1280 x 720) panel, and the battery which has been cut down to 2,300 mAh. Despite that, the Xperia Z1 f is undoubtedly the most impressive 4-inch class Android Smartphone in the market, that is, when it does launch outside of Japan.