Sony Xperia Z-2

Xperia Z2 sports 2.3 GHz quad-core processors, Android 4.4.2 KitKat default OS, 3 GB of RAM, 16 GB internal storage with up to 64 GB of microSD card support and the same 20.7 MP camera found on the Z1.
Reasons Why Upgrading to More Premium
1.      More Camera Modes Xperia Z2 features 4K video recording and Timeshift video on top of other camera modes. It also boasts of a video stabiliser and background defocus on its 20.7 MP camera.
2.      Better Audio Experience Sony came up with the idea of upgrading the audio output of Xperia Z2 to match its great display. Z2 features five different audio engines such as Digital Noise Cancellation, Clear Stereo, Clear Bass, Clear Phase and xLOUD to maximise the dual front stereo speakers.
3.      Larger Display with IPS Now view images and videos on different angles compared than Xperia Z1 using the IPS LCD display technology. See vivid colours with Triluminos and X-Reality engines on various angles.
4.      Better Multitasking Unlike Z1, Xperia Z2 has a larger RAM chipset with 3 GB capacity to sustain more running apps and faster multitasking speed backed up by improved processor cores.
5.      More Power Android 4.4.2 KitKat delivers the improved and all-new STAMINA mode to keep the battery longer than usual. Moreover, Z2 features 200 mAh higher battery pack than Z1.
What Won't You Get
Most upgrades Sony was incremental to improve the display, sound and camera apps. Similar with Galaxy S5, there are great features you won't get from Xperia Z2.
-          Processor cores with 64-bit support
-          Larger microSD card support of up to 128 GB
-          Removable battery unit
-          Magnetic Resonance wireless charging
-          One-hour charging technology