Ainee (https://www.ainee.com) supports the understanding of documents, individual, in a library or grouped into folders in a knowledge base, via a chatbot, categorization and automated summaries (summary, transcription, outline and mind map).

Fashcards offered online (quiz and podcast announced).
Accepts URL, audio recording, excel, pdf, word, ppt, markdown. Internet search tool.

Sharing documents and knowledge bases by link or publicly.

iOS, MacOS, web, and chrome extension apps.
Basis of the open-source project: https://github.com/luyu0279/Ainee

Free and unlimited beta.

Tests from web and iOS versions with resources present on https://www.reseau-canope.fr/ia-en-classe, Artificial Intelligence and Education : Research Contributions and Challenges for Public Policies and Unesco Guidelines and References.