4 ms·

aren't multibillion dollar companies like duolingo built on spaced repetition. Not sure id call it niche.

• joshdavham 2y ago
  Can you name another multibillion dollar company, aside from Duolingo that uses it?
  • apwell23 2y ago
    teachmint ?
    • joshdavham 2y ago
      Never heard of em.
      • apwell23 2y ago
        and?