On paper, the Xperia Z has a battery of 2,330 mAh, slightly higher than Galaxy S III, which have a battery of 2100mAh. But many factors determine battery life, and the Xperia Z powers a display with over two million pixels.
The good news for the Xperia Z is that Sony has developed software called Battery STAMINA mode, which improves standby time by at least 4 times.
The Xperia Z runs Android 4.1 Jellybean, which is a slight disappointment since Android 4.2 is out in the wild. But Sony assures me it intends for the Xperia Z to get upgrades to 4.2 and the next iteration of Android (codenamed Key Lime Pie). Now Samsung have pulled out its 4.1.2 jelly bean update for the galaxy s3.
So which wins?
The Xperia Z actually looks good, and the device is set to arrive by the end of Q1. But Can the smartphone sell as well as the Samsung device? The answer we will reveal in the future. But the mobile phone industry is developing rapidly, rumors now also say that Samsung galaxy s4 might be released this May. Anyway, let us wait to see.