For the total newbies, I'm including several screen shots to show you exactly what you will see onscreen when using PerfectPhoto for maybe the first time.
After you select the Tools/Crop option, you may also choose the type of crop (click the Free icon) before cropping your image. You may also rotate an image by 5° increments.
Scroll down in the Tools to locate and select the Sharpen option.
The top image is the starting point for this tutorial and was obtained by merging HDR output from the native iPhone 4 camera with TrueHDR; the bottom image is after cropping and sharpening as described here. This image is the starting point for the Hydrangea processing tutorial.