They have black/white vision from their eyes. Chemosensors on the tentacles (water-based snails) Smell is their strongest sense. Their senses are all concentrated on the front of their body. They also leave slime trails when the move across a surface that are interesting visible traces and can be quite beautiful.
There are kinds of snails that live on land environments but also those that are water-based and could be kept in a tank (and likely have chemoreceptors).
The large African Land Snails are an invasive species in Germany, and while technically we could get one, we should not
Snails are easy to care for.