I briefly mentioned this Universal app a few months ago, but wanted to mention it again as it continues to improve (and was updated for the iPhone 5 last month). The basic summary of this one is that you get to blur regions of your photo to simulate a big wide aperture of a DSLR.
Big Lens gives you the ultimate in focus and filter tools for your iPhone. Simply focus where you want, with Reallusion’s Big Lens which turns everyone’s iPhone into a professional SLR camera. Snap a picture and then edit it like magic by setting the aperture, changing periphery blur levels, and adjusting background light to create a Bokeh effect with just a few gestures.
Here is a really quick example of what I did for a photo. I first used TouchRetouch (that link is iPhone, also free and iPad versions) to get rid of the extra table on the right side of the photo.
 |
 |
When I took the original photo I’d focused on the coffee cup by tapping my finger on the screen of my iPhone where I saw the cup (this tries to focus and expose for where you tapped). That partially gave me the effect I was looking for, but I wanted a bit more blur in the background, and a ‘coffee house’ look. I opened Big Lens, imported the photo, and selected the advanced mode.
I drew a very rough outline around the coffee cup with the brush and then chose the ‘auto’ option. It did a really nice job. I moved to the next step by clicking the right arrow on the upper right of the screen. I then chose a wide aperture (to increase the blur) and chose the Sepia BG (BG = background) option. I chose the ‘heart’ lens to make the shot happier. 
To really see this lens effect take a nighttime shot with street lights in it.
At this time it was really close to being finished. I used the Focus and Blur brush to tweak a bit around the cup. I also selected the HDR option at the top to brighten up the background.
Final image that used Big Lens.
It’s not a brilliant artistic image, but it gives a good example of what you can do with Big Lens. Currently this Universal app is just $1 over on the iTunes App Store. Easily worth it. Some of the lens effects are really nice. I’m hoping in the future that we get an option to adjust the light source location for the filters that have light effects.
The app also has a few quirks. It is tough to really get a smooth edge around objects such as the coffee cup in this shot (more noticeable in full size image). And every now and then if I blur or focus a region I’ll end up with larger ‘blocks’ of a focus/blur region. Hopefully a smoothing feature for the edge regions gets introduced at some point. The ability to selectively blur portions of the image still make this app one of those that is nice to have in your iOS tool belt.
There is a nice demo video on YouTube. And here is another image in which I made use of Big Lens with one of the ‘Light effects.”
