Mushrooms, mosses, invertebrates and even some plants seem to rely on specific small features that aren't always captured in photos of the thing to identify accurately down to the species level.

I'm using a national app, probably tuned on national data, so your mileage may vary, but my experience has been good: the app sees different and more nebulous features than what I have been trained to see by the mushroom experts at our foraging association. I never eat anything based on the app only obviously, but I often get more specific IDs, which usually seems right when I look up the mushroom it suggests.

Russulas, for instance: in my country, there are no poisonous ones, but there are at least 90 varieties and experts will often need DNA analysis to place them confidently. The procedure for determining edibility recommended by the foraging association is, once you're certain it's a Russula, to taste a small piece and spit it out. If it has a burning sharp taste, it's not food.

The app has been very good at predicting whether I'll experience that burning sensation, and all from signs that are invisible to systematic description (I won't rule out that an expert can also spot subtle differences between a sharp green russula and an edible green russula, but they probably wouldn't be able to describe it).