Now, details of the Sony Xperia Z4 Compact and Z4 Ultra have leaked, although we'd advise taking them with a larger than normal pinch of salt; since they suggest that the Z4 Compact will have better than flagship specs, while the Z4 Ultra will have a gargantuan 6.44-inch screen.
The leak, first picked up by Android Origin, predicts the Xperia Z4 Compact will come packing the Qualcomm Snapdragon 810 processor chip - also a possibility for the flagship Xperia Z4 - and 3GB of RAM. Sony may now be known for featuring flagship specs in its Compact smartphones, but to make it just as, if not more powerful than the flagship device seems unlikely.
The Z4 Compact is rumoured to have 32GB of internal memory, a 20.7MP rear camera, 5MP front-facing camera, IP68 dust- and water-resistance and wireless charging support. The display should be kept at 4.7in but will increase to 1080p resolution and a 3000mAh battery is expected too.
The Xperia Z4 Ultra meanwhile is said to come sporting a 6.44in display, like its predecessor, but this time it should have a Quad-HD resolution (reaffirming a previous leak). It's also rumoured to be powered by the Snapdragon 810 chipset and 3GB of RAM. The leak suggests it will feature a 16MP rear camera and a battery with a capacity between 3500 and 4000mAh.
The Z4 Ultra also seems to be gunning for the Samsung Galaxy Note 4, with Android Origin's source claiming that it'll support stylus input.
Some reports suggest that the Xperia Z4 flagship will be unveiled at CES in January 2015; however, the Z4 Compact and Z4 Ultra will reportedly be delayed until later in the year, due to shortages of the Snapdragon 810 chipset.
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