Asus has revealed the Padfone Infinity, the third iteration of its Padfone docking phone and tablet combi devices, taking things up-market with a 5-inch 1080p handset.

Taking to the stage at Mobile World Conference in Barcelona, Asus CEO Jonney Shih unveiled the new Padfone.

With its all-new aluminium alloy unibody frame design, the "metallic miracle" joins the ranks of the previous Padfone models, which have so far taken some time to go on sale. 

The Padfone line of devices sees you slipping the smartphone into the rear of a host tablet "Station" that boosts battery life and gives you the advantage of the big-screen tablet experience running from the phone's brains. 

The new Padfone Infinity will offer a 5-inch 1920 x 1080 pixel display with 441ppi on the smartphone side of things and a 10.1-inch, fingerprint-resistant display on the Station.

There's a 13-megapixel camera with f/2.0 aperture on the rear of the device which is capable of Full HD video recording at 30fps. There's also a 2-megapixel f/2.0 camera on the front.

Audio is another hot topic: the Padfone Infinity features the third-generation SonicMaster technology which Asus claims is louder and bassier but with less distortion. There's an 80mm diameter speaker on the tablet to amplify the sound when the two are paired together.

The smartphone will be powered by the Qualcomm Snapdragon 600 quad-core chipset, clocked at 1.7GHz and backed by 2GB of DRAM. You'll also get 4G LTE connectivity and 64GB of flash storage on board.

Battery life can last out for 410 hours on standby, but pop the Padfone Infinity into its tablet dock and battery life increases three fold. That means up to 57hrs of 3G usage with the two devices linked, Shih claims.

How much for this high-spec device? It'll be 999 euros (£879) for the full package, due on the shelves in April.

UPDATE We've just received UK pricing of "around" £799, but Asus then says that exact pricing will be announced closer to launch date.