Recommended: Exif Wizard, an iPad app that tells you the EXIF data in the images on your ipad.

Like this:

..and there’s a whole lot more info. As long as you have not stripped out the EXIF data while saving (Lightroom, etc, offer this possibility), you will be able to go back to your saved images and answer the question “what settings, equipment, etc was I using for this?”. Which for pros as well as beginners is an important question.