This post is long overdue, but I've been using Tarte's natural lip sheer for several months now. It's advertised as a cross between a lip balm and a lip gloss, and it pretty much delivers on that. It doesn't feel quite as moisturizing as some other lip balms that I've used, but it is more moisturizing than a regular lipstick. This lip sheer has an SPF-15 rating, and comes in a variety of shades named after days of the week. (I've got the Thursday, which is a light rose shade.)
I try to stay away from things that are super chemical-laden, so I appreciate that this has no parabens, phalates, or sodium laurel sulfate. I generally don't like wearing lots of makeup, so for me, this lip sheer is a perfect way to get some moisture and a little color at the same time!