I usually use it on my lower lashes, and it's also useful when my lash extensions start to fall apart and gaps appear! I always wear mascara on my lower lashes because it makes a huge difference in the look of my makeup, but personally, there are some key points to using it on the lower lashes: it doesn't create dark circles, it comes off easily with makeup remover, it doesn't clump, and it gives a moderate amount of volume and length. Not only does it not create dark circles, but being waterproof yet removable with makeup remover is extremely important, and this product ticks all the boxes, so I've already used several bottles. Of course, when my lash extensions start to fall apart and gaps appear, it fills them in naturally and doesn't put any strain on the extensions when I remove it.