Updated: Sony Xperia Z4 release date, news and rumors

Xperia Z4: release date, design and displayIt might not seem that long ago since the Xperia Z3 was released, but with Sony's rapid release schedule for its flagship smartphones the rumour mill has already been working overtime.We've started to hear plenty rumours about Sony's next flagship, including one report which reckons the Japanese firm will return to an annual launch of its top device, ditching the recent trend of every six months, though not until after the Z4 launches.Updates: Passing J