The 7.0 MPX iPhone application which claims to increase the quality of your iPhone camera from 2MP 3MP to 7MP. At the time of writing it is available on iTunes for £0.59.
I was dubious about buying this, but read some of the reviews and it said that it worked. Some other reviews said it didn't, but I chose to listen to the good ones - I shouldn't have.
Put simply this does nothing to improve the quality of your photos. Some reviews on iTunes stated that you don't see a difference until you transfer the photos onto your PC Mac. After seeing no difference in photo quality on the phone I decided to copy them to my PC. Still no difference other than they are slightly brighter and larger, scaling them down to the same size as the standard photos makes no difference.
Apart from the fact it doesn't work (in my opinion) it is easy to use the camera, but it takes longer than the normal camera to process the photos you have taken, which isn't worth the wait since it isn't any better. It also has a timer, which is something positive I suppose.
Overall I would highly recommend staying well clear of this. It is £0.59 to lose a few megabytes of your phones memory. Why this is allowed to be sold on iTunes I have no idea.