High dynamic range (HDR) imaging is a set of techniques that allow a greater dynamic range of luminance between the lightest and darkest areas of an image than current standard digital imaging techniques or photographic methods.
The Samsung Omnia 7 is another device which also features this technology, This allows well lit, beautiful pictures even in variable light.
This wide dynamic range allows HDR images to more accurately represent the range of intensity levels found in real scenes, ranging from direct sunlight to faint starlight. This technique which was only applied to photos in post-processing previously, However the iPhone introduced the creation of HDR photos right on the device.
Check out the photos below from Manan Kakkar, a blogger, who demonstrates the advantage of HDR over normal pictures