Description from the AppStore: Auto Adjust is a lightweight utility for performing "Contrast Stretching" (normalization) on the all too frequent dim or white, washed-out image that the iPhone built-in camera takes.
Typical Contrast Stretching (Auto Levels or Auto Contrast in Photoshop) interatively analyze an image to find the brightest and dimmest pixels (in greyscale). However, an otherwise dark image with one bright spot will span the entire range from 0 to 255 and no adjustments will be made. This limitation is overcome by processing the full histogram of the image and doing some discrete calculus.
Images are processed and saved at their original resolutions. This can lead to some longer processing times on 2048x1536 iPhone 3GS images but it's worth the wait!
AppStore Link: Auto Adjust - Price £1.19/$1.99
Editors comments: Although a little overpriced, I found this app very useful for quickly correcting my poorly exposed iPhone photos. This app is not another one of those flash emulators, but allows you to correct shots with strong high or low lights, which as my sample shot below shows, the white walls of the house has affected the exposure which has been more evenly balanced with in seconds by using Auto Adjust.
Above: Original photo on the left, and the Auto Adjust version on the rightThere is a free light version of this app [Auto Adjust FREE], however it only saves at 480x320 and does not have the fine tuning (intensity) slider bar of this full paid version.
There is one major bug that I have found with this app, and it seems to be one that is becoming more common, and that is it gets the orientation of the photo wrong, and so you will need an app top rotate and correct the saved photo.
All-in-all I found this a useful app for quick exposure corrections, and one that I will continue to use, and gets 3 stars out of 5 from me. It falls short of getting 5 stars due to the above mentioned bug and its price, which I would have liked to have seen at £0.59/$0.99 due to it being a one trick pony, albeit a very good one trick pony.