I broke my thumbnail about 1/4 " and it's belong the quick so when Marilyn was here today I asked her to get me some superglue. Not the best solution since it can get gloppy, but I told her to look in the fingernail section. She found a "paint on" superglue that is very thin, you put in on like nail polish. I put on two coats and you can't even see it by the tear.
It comes in a bottle smaller than nail polish, pink label, called "Kiss Brush-On Nail Glue" and I paid $5.79. A bit pricey, but this bottle will see me into the next decade. I've even tested it by trying to (gently) separate the nail at the tear and it's holding tight.
So far, I give this product four stars!