In addition to taxa hierarchy, keying out features would be great. In this situation, there are boxes you can check off for size, color, presence or lack of certain key features. Visual algorithms can only do so much. With the iNaturalist app, I can often get to genus level (unless Asteracea, the plant family of the typical yellow flower, observations are involved). After that, books and certain measurements or knowledge of anatomy are needed.
Too, you can have taxonomic view with the “children”? list of species and subspecies but still not come closer to identifying a species. For example, for my particular interests of plants, I can get to “Lupinus” genus, but that genus also has 2-3 subgenus and hundreds of species, even if we know which species are more likely present in a region, harder information is needed to narrow choices down further.
Thus far, the only way to truly confirm a species is to use a book that helps you key out the species. To my knowledge, no mobile app exists to get more technical on species and spp. identification. Whereby you can use it as a manual for identification. Some apps come close but are lacking complete families. iNatualist comes closest to species identification because it sources identifications from the crowd (of often knowledgeable, talented group of professionals and amateurs) and sometimes the Guides features (as intended but often incomplete) can get close to this.