Samsung's Galaxy S4 debuts with eye control and BYOD features

New screen, better battery life and performance but Samsung shares fall slightly after launch

Samsung unveiled its latest smartphone, the Galaxy S4, in New York last night

Lighter and slimmer than its predecessor the S3, the S4 also has a slightly larger 5in HD AMOLED screen with a resolution of 441 pixels per inch, equal to that of the Sony Xperia Z.

Other vital statistics include the 13 megapixel camera (a major advance on rival iPhone 5's 8 megapixels), a 1.9GHz quad-core Snapdragon 600 quad-core processor from Qualcomm in the US or a 1.6GHz the Exynos 5 Octa 8-Core processor elsewhere, and 16GB, 32GB or 64GB of storage - expandable via MicroSD card to 96GB or more, should such massive amounts of storage be required.

Then there's the 2600 mAh battery, which is 20 per cent larger (and presumably slower to drain) than that of the S3. As well as being more powerful, the new processors are more efficient than their predecessors, which should also add to battery life.

Connectivity is via LTE, Bluetooth and Wi-Fi and there is support for NFC, making it compatible with Google Wallet.

A more powerful, sleeker smartphone than the S3, then, in a slightly smaller (130g, 7.9mm thick) polycarbonate-cased package. However, the main advances are to be found in the software.

Boasting the ability to control aspects of the phone by eye or by hovering a finger over it, the Android-powered S4 may offer a new model for the way that we interact with our smart devices - or it may prove to be an annoying gimmick. However, it is certainly innovative and in the battle of the smartphones demonstrating innovation is all-important.

"Samsung Smart Pause enables you to control the screen by where you look. When you are watching a video, the video pauses when you look away then it starts right up again when you are back," a Samsung spokesperson said, adding that Samsung Smart Scroll "recognises your face looking at the screen and movement of your wrist and then scrolls the pages up or down accordingly."

There is also a language translator that understands nine languages and can translate between them speech-to-text and text-to-speech, and the dual cameras (there's a 2 megapixel camera up front) allow you to take two pictures at once - one of yourself and one of your subject - or more usefully to superimpose your image on screen during video chats or conferencing.

Samsung's Galaxy S4 debuts with eye control and BYOD features

New screen, better battery life and performance but Samsung shares fall slightly after launch

One business feature included in the S4 is Knox, which meets the BYOD challenge by separating business and personal use of the mobile device in similar fashion to BlackBerry Balance, allowing additional security for mixed work and personal usage.

Prices for the new phone have not yet been released, but it will be available globally from the end of April and Samsung says that 327 mobile operators in 155 countries will carry it.

Initial reactions to the S4 have been mixed. While praising the new screen, battery and processors, some analysts claimed that the real advances are limited to some slightly gimmicky software.

Following the launch, shares in Samsung fell 1.7 per cent in early trading in Seoul on Friday amid worries the market might be becoming saturated, and have remained slightly down since then, at time of writing.

The Galaxy S4 will go head-to-head with the likes of the Apple's forthcoming iPhone 5, the HTC One, BlackBerry's Z10, Sony's Xperia and Nokia's Lumia. On current trends it is likely to outsell them all.