Retain vs StudyGlen

Retain is a flashcard app for Android, iOS, and the web. It uses AI models and learning science to create personalized learning plans: learners set a goal and receive a plan, and the AI can generate flashcards from uploaded PDFs. The site lists PDF, PNG, and JPEG uploads; its onboarding also names images, YouTube videos, GoodNotes notes, and Notion notes as learning sources. Card options include cloze, image occlusion, and custom Anki types, with mixed card formats and study modes and adaptive review. Decks and individual cards can be shared by link. The company also offers B2B licenses to businesses and educational institutions, with pricing available by contacting Retain. Its privacy policy says usage data, including flashcards and learning progress, may be analyzed in aggregated and anonymized form to improve AI models and algorithms.

StudyGlen turns study materials into AI quizzes, flashcards, educational comics, and live quiz competitions. It accepts PDFs, text, images, handwritten notes, YouTube links, and Anki decks; quiz creation can use image OCR and YouTube captions. Flashcards use FSRS spaced repetition, offer basic and cloze cards, and can be studied in smart, sequential, or shuffle modes. The free tier includes one quiz or flashcard daily, one lifetime comic, and two question regenerations per day. Quiz generation can also be tried without an account, with five free questions and no card required. Paid packs are one-time purchases starting at $4.99; the Mini Pack has 10 study credits, and each credit generates one complete quiz or deck. Quizzes can be exported to PDF, Word, CSV, Anki, or QTI. StudyGlen supports 41 content languages and has Android, iOS, and web access. Its mobile apps allow offline review and sync ratings when connectivity returns. Uploaded materials are removed from active systems after processing, though backups may persist for up to 30 days.