I built FlipCards – a flashcard app with variations to improve learning
Hi HN, I’m Felipe, a 9-5 developer aiming to become a full-time indie hacker. I struggled with flashcard apps that focus on decorating cards instead of learning concepts, so I built FlipCards to solve that problem. What it does: FlipCards lets you: - Create cards for any concept (math, language, coding, etc.) - Add multiple variations per card – the more variations, the better your understanding - Study smarter – the algorithm randomly selects variations so you can’t just memorize Q→A patterns Why it’s different: - Most apps use reverse cards (Q→A, A→Q). FlipCards uses variations to…
In plain words
FlipCards is a flashcard study app designed for learning concepts across subjects like math, languages, and coding. It lets users create cards with multiple variations of the same concept, which the app presents randomly during study sessions to prevent pattern memorization. The app uses the SM2 spaced repetition algorithm for long-term retention. It's aimed at learners who want focused concept mastery rather than decorative cards. A free tier offers limited access, with paid annual and lifetime options for unlimited decks and cards.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
Hi HN, I’m Felipe, a 9-5 developer aiming to become a full-time indie hacker. I struggled with flashcard apps that focus on decorating cards instead of learning concepts, so I built FlipCards to solve that problem. What it does: FlipCards lets you: - Create cards for any concept (math, language, coding, etc.) - Add multiple variations per card – the more variations, the better your understanding - Study smarter – the algorithm randomly selects variations so you can’t just memorize Q→A patterns Why it’s different: - Most apps use reverse cards (Q→A, A→Q). FlipCards uses variations to reinforce concepts in multiple contexts. - Powered by the SM2 spaced repetition algorithm, scientifically proven for long-term retention. Pricing: - Free – 1 deck, 3 cards, 1 study session - Annual – $20/year for unlimited decks and cards - Lifetime – $50 one-time for unlimited everything I built FlipCards because I kept getting stuck decorating cards in other apps. Now I can create as many variations as I want, and the algorithm mixes them for me. I’d love feedback from the HN community: - Does this approach to flashcards make sense? - Would you use an app like this for learning? Try it here: https://flipcardsapp.vercel.app Thanks, Felipe
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