With a massive 6.4in display, Sony Xperia Z Ultra is not of tablet proportions but dwarfs some of the larger Android smartphones - it's also completely waterproof.
Sony has unveiled the Xperia Z Ultra, a jumbo Android device that's stolen the title of world's biggest smartphone from the Samsung Galaxy Mega.
As well as being on the larger side, with a gigantic 6.4in display, Sony's Xperia Z Ultra is also the slimmest large-screened device of its kind. It's also entirely waterproof.
The original Sony Xperia Z released earlier this year has a sizeable 5in screen of its own, but Sony is now looking to challenge Samsung's dominance of the 'superphone' and 'phablet' markets.
Although the new Ultra model is too small to be considered a phone/tablet hybrid, it dwarfs many of its Android rivals, including the Samsung Galaxy S4 and HTC One. The largest of Apple's smartphones, the iPhone 5, has only a 4in display.
Calum MacDougall, director of Xperia marketing at Sony, said: "The Xperia Z Ultra is the most exciting revolution in large-screen smartphone entertainment devices with both the slimmest and largest full HD smartphone display in the world."
"We're already bringing the best of Sony technology and design across a range of premium smartphones and tablets, and now we're bringing this same offering to the large-screen smartphone, setting a new standard for others to follow," he added.
The Xperia Z Ultra has an eight megapixel camera, a powerful 2.2GHz quad-core processor and 16GB of internal storage.
It measures 6.5mm thick and weighs 212g, which is roughly 100g more than the iPhone 5 but just 13g heavier than the Galaxy Mega, which has a smaller 6.4in screen.
In water, it should survive being submerged 1.5m deep for up to half an hour.