I would recommend something like what the above suggested or a slider case that keeps the entire iPhone enclosed. I use
http://store.theiphoneblog.com/belki.../4A25A2571.htm but generally keep it clipped onto my jeans. I rarely keep it in my purse. If she has a purse that's loaded with stuff, something that keeps the screen accessible may be
convenient because it will take less time to answer the phone after finding it; but it may also be more dangerous for her phone. I personally prefer the naked feel when I use my iPhone so... yeah. My mom uses something similar as above and her phone has survived the depths of her purse, so it's probably fine
