The Xperia Z2 is Sony's latest flagship smartphone, and the replacement for the six-month old Z1. It utilizes almost the same IP58 rated aluminum and glass build as the Z1, but sports a slightly larger 5.2-inch display. It's also been upgraded to Qualcomm's Snapdragon 801 processor and is now running on Android 4.4 KitKat. Worth upgrading? We find out.