Photoshop is now available on your iPhone and iPod touch, and it's completely free. Cropping, trimming and making rudimentary tweaks to your photos with Adobe's software costs nothing to try, and it's not as pointless as you might think.
Even if the only thing you do with the app is crop a photograph before sending it to Facebook or Twitter, it's worth downloading. A touchscreen provides an intuitive way of cropping images, and there's a bunch of processing options, such as exposure, saturation and tint controls, as well as some pointless filters.
Once you've finished cropping genitals out of your pictures, you can save your work as a new JPEG file and upload it, via the app, to Adobe's photo-sharing service, Photoshop.com, or somewhere else.
There's no option to get rid of red eye, but then the iPhone doesn't have a flash, so who cares? Also, don't expect even the slightest bit of advanced functionality -- you can't add text, and you can't copy and paste. It's purely and simply a tool for quickly touching photos up before uploading them to the Web. But it's free and ridiculously easy to use, so it's worth downloading.