Well, Ron, sometimes when you download a model from the web, you might find that textures won't "stick" to it. With UV Mapper, you can apply the UV coordinates that make the texture stick. Also, for example, let's say you turned Posette's entire body invisible except for her head. Then you used the selection tool to apply a new material to her head, and you named that material "Head". You could then create a prop of her head, and export it as an OBJ. You open that new "Head" prop in UV Mapper, and export a texture template of it. You could then create a large, highly-detailed texture map in Photoshop or whatever, and apply it to the Head material you created on the original Posette. I'm sure there are many other uses as well.