Sony Xperia T3 Sony Mobile

Sony Corp. (NYSE: SNE) claims its newly announced Sony Xperia T3 is the world’s thinnest smartphone with a 5.3-inch display, which would put it in the category of “phablets,” devices that are considered a hybrid between smartphones and tablets due to their size.

The Sony Xperia T3 boasts a thickness of just 7mm, which is far from the thinnest smartphone in the world. Currently the Gionee Elife S5.5 earns that accolade with its 5.5mm thickness and 5-inch display. But Sony seems to have forgotten many of its other “world’s thinnest” devices, which are actually thinner than the Xperia T3.

The Sony Xperia Z Ultra was announced in June 2013. It features a 6.4-inch display with a 1920x1080p Full HD resolution. It was marketed as the world’s thinnest Full HD smartphone with a thickness of just 6.5mm. The device was called an "an engineering marvel" by Phone Area. The Sony Xperia Z2 tablet was announced in February 2014, featuring a 10.1-inch display. It was marketed as the world’s thinnest waterproof tablet with a thickness of 6.9mm. Both devices are notably thinner than the Sony Xperia T3 and have larger displays.

Sony got very specific with the Sony Xperia T3. It was designed to be Sony's thinnest device at its particular display size. Another popular device with the same display size is the Samsung Galaxy Note, which is considered quite thick at 9.65mm.

As most manufacturers aim to make their devices larger these days, the Xperia T3 does not appear to have many rivals. The Galaxy Note, while very popular in its heyday, is now more than two years old and is out of market rotation.

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