Sony XPERIA Z1 is still one of the best smartphones on the market. Only this XPERIA from Sony Mobile Compact line has metal body, so many people still love it and use it. 2.2 GHz Qualcomm MSM8974 Quad Core and 2 GB RAM are enough for Android 6.0 Marshmallow. And it is less than two years from time, when Sony Mobile Company launch this luxury phone. It has very similar specification to XPERIA Z2, which get upgrade to new Android operating system and thanks to lower display resolution (in XPERIA Z1) can Android 6.0 Marshmallow run pretty good in our smartphone. There is no reason (except business) to no upgrade for this phone... Share it, sign it and Sony Mobile company will change it.