The world's thinnest phone, rated by the Guinness Book of Records, is now on sale in the US. The smartphone is just 5.5mm thin – that's thinner than a pencil.

The Blu Vivo IV is on sale now in the US for $299, or around £183, which is really well priced considering all the power that's packed into the slender form.

The Vivo IV is powered by an 1.7GHz Octa-core CPU backed by 2GB of RAM and ARM Mali 450 graphics. The screen is a 5-inch 1080 x 1920 Super AMOLED display with 440ppi which is covered in Corning Gorilla Glass 3. On the rear is a 13-megapixel camera with a 5-megapixel front-facing selfie snapper with 95-degree wide angle lens. There will be 16GB of storage built-in without microSD expansion and a 2,300mAh battery.

Unfortunately the handset will come running Android 4.2 Jelly Bean but that apparently can be upgraded to 4.4 KitKat. The Blu skin offers gesture controls, Dolby Digital DTS sound and a pro-grade equaliser.

The Vivo IV is HSPA+ ready for up to 21Mbps speeds. This isn't as fast as the Samsung Galaxy S5's 42Mbps, for example, but at that price you can't really expect it to be. It will also work with Bluetooth 4.0, Wi-Fi, Hotspot and micro-USB 2.0.

The Blue Vivo IV is available now in the US for $299 which is about £183.

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