She should look at the ingredients! Ingredients are always key when it comes to buying products. I would suggest she buy one that has the most natural ingredients and that she buys one that fits her needs the most. If she has supper dry lips then I would suggest going for maybe a thicker lip balm if she is going for a kind of lip stick ish look I would go for one that kind of has a lip gloss affect.
I hope this helped! :-)
