Finally, a smartphone battery that lives up to its claims: Sony's Xperia Z3 lasts for TWO days - even when streaming videos and making calls

Sony unveiled its Xperia Z3 smartphone in September with the bold claim that its battery lasts an almost unprecedented two days.

And while manufacturers have a tendency to exaggerate about such features, reviews of the device suggest Sony wasn’t lying.

Initial testing revealed that not only does the device last, on average, for 48 hours before it needs charging again, this is the case even when streaming music, making calls and watching videos.

This involved using the device for approximately five hours over a 24-hour period, for a range of ‘typical usage scenarios’.

They included calling, texting, surfing the web, checking social networks, playing games, using the camera, listening to music and streaming video.

In tests, the phone’s default settings were applied, which included setting the display brightness to 100 nits, with battery stamina mode turned off.

Nits are used to determine the brightness and readability of a display, and the Xperia ranges from four to 713 – meaning 100 is towards the dimmer end, but not at the minimum.

During personal tests, the phone lasted for 45 hours before it ran out of energy completely.

A number of other tech sites have also managed up to two-day battery life during tests.

Engadget’s James Trew, for example, said: ‘The Xperia Z3 performs well and has epic battery life.

'In my personal usage, I regularly got two days of full use, or so near to two days that I'm loath to mark it down for the odd 10pm finish on the second day.’