The little tiny white snails that can sometimes be annoying at collonista snails. Check them out with a search and this may help you ID them. They are harmless but the population can rise to ridiculous levels. In my experience, the darker coloring on collonistas ten to be thinner or smaller than what I see in the 4th picture you posted. There have been a few folks in the past that had banded trochus snails reproduce in their system and if that's what they are, you're a serious winner.
One of the worst snails to get is a sundail snail. They are predatory and have really dark, distinct markings on their shells. One easy way to differentiate between collonistss snails and sundails is size. Collonists snails stay tiny and you usually see them all over the glass when the lights turn off or hanging out right at the water line of the aquarium during the day. Do some poking around and see what you think. It's been a while since I've heard about sundail snails in the local community. Another way to tell if it's a sundail is that they eat zoas. Do you have any zoas in your tank? Are they doing good? Any of these snails hanging out in the area?
You finding them all over your glass is a good sign in my opinion. Good guys eat algae and other films on glass so that's where they'd be. I'm not trying to scare you by mentioning them. Rather, they are a bad pest and it's good to be aware of them. A friend of mine actually made the decision to add a sundial snail that came in on a frag to his system thinking it was a baby good guy. I don't think what you have is a sundial; I think it's a trochus of some sort. The 2nd and 3rd pic seem to indicate the dark flammules are in "V" and that's typically seen on the good guys.
