The BlackBerry Aurora's rear camera comes with an electronic aperture (E-Aperture in the camera app). This allows the camera to mimic the effect of a variable aperture lens. You can choose an aperture ranging from F2.8 to F44. Choosing a very high aperture value (higher f-number) will limit the amount of light that passes through. This will tell the camera to shoot at very slow shutter speed to compensate for the lack of light. This allows photographer to achieve some very nice effects that you usually achieve using an ND filter and a very high aperture value in DSLR cameras. For example, you can put your BlackBerry Aurora on a tripod and take a picture of flowing water. However, unlike a conventional mobile phone camera that would take a sharp image, you can make the water look very smooth, giving the water a beautiful look of flow.
A tripod is obviously necessary because it will take time until the image is captured, maybe a few seconds or so. The BlackBerry Aurora camera app will show you the progress in percentage, which indicated how much time is left until the image is fully captured by the camera. You can cancel it at anytime by pressing the 'X' button.
It's a really cool feature that allows you to be more creative and come home with some amazing shots that other people just won't be able to capture with their mobile phones, no matter how high-end their phones are.
Here is a cool video that demonstrated this amazing feature [video removed by the user, so I removed it]
As you can see, you can achieve some stunning image effects that until now you could only achieve using a phone with ND filter or a DSLR camera with special accessories. The problem is that without an ND filter, it's impossible to achieve this type of photo using regular equipment, and by that I mean almost any phone out there. If you need to shoot water flowing and make it appear silky smooth in the image, you need to be able to control the amount of light that reaches the sensor. The problem is that shooting at bright daylight will trigger a very fast shutter speed. A fast shutter speed means that the subject (in this case, the waterfall), will appear very sharp. By using the Electronic Aperture, you limit the amount of light and telling the camera that there is not enough light. The camera than changes the shutter speed to a slower one, allowing you to achieve this desired effect.
Great advantage for the BlackBerry Aurora, which until now I wasn't excited about its specs, but it's nice to have some really nice camera features. Of course this feature isn't just for shooting silky smooth "creamy" flowing water effect of waterfalls, and it opens up the way for many other creative effects for long exposure shots which are limited only by your imagination.