Samsung on Thursday premiered its latest flagship phone, the Galaxy S4 in New York, which sports a bigger display and is lighter and thinner than its previous model.

The S4 - which Samsung preceded with a marketing blitz that drummed up industry speculation reminiscent of some of Apple's past launches - will be available globally in April. Samsung said all major service providers will sell the phone but it didn't say anything about prices.

Samsung held the global launch event in the United States in the hope of regaining the lead in the crucial market. Apple's U.S. sales outstripped Samsung's for the first time in the quarter ending in December, even after Samsung's eye-watering advertising spend of $400 million stateside.

Samsung said the Galaxy S4 will sport a bigger 5-inch display than the S3's 4.8 inches. It's a full HD display (1920 x 1080), giving it a pixel density of 441ppi, outdoing iPhone 5's 326ppi Retina Display, although pixel density doesn't always mean a better screen.

The device also has a 13 megapixel camera, compared with the S 3's 8-megapixel.

As Samsung attempts to squeeze as much profit from its smartphone as possible it is using its own Exynos 5 Octa chip to power the Galaxy S4.

The Exynos 5 Octa is technically a quad-core chip, with eight cores at its disposal. The ARM architecture being used is called big.LITTLE, and the phone can make use of a 1.8GHz quad-core processor for heavy work like 3D gaming and HD video, but can also rely on a 1.2GHz quad-core processor for less intensive tasks, like text messaging and Twitter.

The CPU will be paired with 2GB of RAM, and come in varients of 16GB, 32GB and 64GB with the option of upgrading via a microSD card slot. It will be available in black and white.

The newest features involve different options for navigation. For example, if the phone senses someone is looking at the screen, the user can tilt it forward or backwards to scroll up and down a web page.

That feature falls slightly short of what some consumers may have expected after the New York Times reported that the phone would be able to scroll automatically by tracking readers' eyes.

But what it can do is sense when it has someone's attention. When a video is playing, for instance, the stream will automatically pause if the person glances away and it will restart when the eyes refocus on the screen. The latest phone also has a sensor that lets users move their hands to the left or right to scroll between different websites for example.

Presented by Adam Justice