The bokeh effect, or background blur, is a highly valued feature among portrait and macro photographers, as it allows you to focus on a specific subject in a photo. The Nokia 808 PureView has SLR like bokeh thanks to its very long focal length of 8.02 mm. Typical mobile phone cameras have a focal length of 4 mm.
The longer the distance between your subject and the background, the more powerful the bokeh effect. For the optimal bokeh effect, the subject should be less than 0.5 metres away from the camera.