Mobile technology giants Sony and Nokia have renewed the battle over the smartphone market, announcing new devices at the Mobile World Congress in Barcelona, Spain.
Japanese handset maker Sony unveiled its Xperia Z2 smartphone and tablet range, which will introduce 4K high-resolution video technology to the mobile market for the first time.
The Z2's 20.7 megapixel camera will offer four times the detail of an HD camera and will be the world's first waterproof smartphone and tablet, according to the company.
The new device will also feature digital noise cancelling technology and is the slimmest and lightest phone and tablet, says Sony.
The Z2 will go on global sale next month.
"With Xperia Z2 we have taken our premium Z series to the next level, delivering unique experiences that only Sony can offer," said Kunimasa Suzuki, president and chief executive, Sony Mobile Communications.
"We have redefined the smartphone once again through our camera. Xperia Z2 offers an innovative experience that captures memories in stunning detail through 4K video shooting, or offers new ways to use the camera with our unique Xperia camera apps."
Sony also announced details of its mid-range Xperia M2 smartphone, featuring waterproof technology and powered by Android. The M2 will go on global release from April 2014.
The new devices emphasise Sony's commitment to hardware improvements as the company aims to consolidate its position behind Apple and Samsung in the smartphone market.
Finnish company Nokia also announced the release of its first ever Android smartphones aimed at consumers in emerging markets.
The Nokia X, X+ and XL will use Google's Android operating system, as seen in Sony devices, rather than Microsoft's Windows Phone technology featured in Nokia's Lumia range.
However, the low-cost Nokia X devices will not feature many of the Google services that come with Android, and instead emphasise Microsoft services such as Bing, Skype and Outlook .The X range will also feature the resizeable home-screen tiles, resembling those on Windows Phone.
