The program was built on Adobe AIR and the creators boast that; among other things. TouchUp Pro has a nice clean interface that lets you get right down to business without too much mucking about.
You can load pictures directly from your camera or your photo library and adjust the basics like contrast, brightness and saturation. You can also play with some fun effects like a few different sepia tones, high and low saturation settings and black and white.
esDot Development Studio says that you can expect updates to the program soon, including more filters and an advanced effects editor.