It has been reported that the dimensions for this particular smartphone in question are 129.5 x 64.5 x 9.4 mm. (phoneradar.com)
The leaked specifications of the Sony E5663 hint that the mysterious smartphone in question could be the successor of the Xperia Z3 Compact i.e. the Xperia Z4 Compact owing to the 4.6 - inch screen size. (techtimes.com)
According to a post on the official Sony Xperia Product blog, the most interesting of the new highlights hitting the smartphones in question is the glove mode, a feature that allows users to work their touchscreen device even with heavy mitts on. (techshout.com)