The Sony Xperia Z1 Compact might be small, but there's a quad-core 2.2GHz Qualcomm Snapdragon 800 processor under the bonnet with 2GB of RAM.
Performance was not an issue during our time with the Sony Xperia Z1 Compact. Although its size meant that it often felt like a mid-range phone, the handset delivered high-end performance. Apps opened quickly, TV streaming and gaming were smooth, and we noticed no performance hiccups during our time with the phone, as it seemed to match, if not improve upon, the performance of the Xperia Z1.
In fact, the Sony Xperia Z1 Compact came out on top in benchmark tests, scoring 35,071 using the Antutu benchmarking tool. Not only does this mean that the phone beats the performance of the Xperia Z1, it also ranks the phone higher than the Samsung Galaxy Note 3, HTC One and LG G2 smartphones.
Sony has preloaded the Xperia Z1 Compact with Android 4.3 Jelly Bean out of the box, but has already promised that an update to Android 4.4 Kitkat will appear in the coming weeks.
That said, you'd struggle to notice the lack of Android 4.4 Kitkat given Sony's custom user interface (UI). While we've never been fans of Sony's UI skin, we find it more useable than Samsung's Touchwiz or HTC's Sense alternatives, with Sony's offering a unified look across homescreens and menus.
While the UI is useable, Sony has added its own apps into the mix too, most of which we didn't find ourselves opening more than once. Sony's Music and Video Unlimited apps went unused, for example, as did the firm's custom Album app, as we opted for Google's alternatives instead.
However, thanks to Sony's stripped-down UI and lack of widgets, it's very easy to customise the phone so you only see the apps that are relevant to you. Our favourite feature of Sony' software was perhaps the ability to zoom out to see all of our homescreens and apps, and making it easy to arrange the user interface.
Next: Camera, battery and storage.
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