[antisemiotic]

I think it really helps to be taught by someone who knows what they're doing. Where I live (Poland) it's common to have this knowledge passed down in families. I wouldn't dare to pick up anything based on a picture in a book.

[felixyz]

There are apps that lead you through a series of questions (pores/gills, cap shape, etc) to try to identify a mushroom. App + book + internet for anything that is remotely uncertain is a pretty good avenue if you don't have anyone to teach you. And yes, it's crucial to inspect every single mushroom before eating it and discard anything that one isn't 100% sure about.

[jtbayly]

Have you ever used bird identification apps like that? I would never in a million years trust an app to tell me what is safe to eat. To learn? Yes. But not to eat.

[antisemiotic]

Hm, I was already starting to think about some sort of portable chromatography kits to identify toxins in the field, but I guess your solution works too.