Most flashcard apps publish a deck and call it done. We publish the deck, the difficulty model, the source citations, the community signal, and the gate every card had to pass to ship. Read on — or jump in.
Every domain has a published maturity tier. We won't sell you a paywall on a domain that isn't ready to be paywalled — and we tell you what the tiers mean.
Six gates between a draft and your queue. A card that fails any of them is rewritten or dropped — drafting state never reaches you.
Every card has an EigenScore — an ELO-style difficulty rating, on the same 800–2400 scale chess uses. Your own EigenScore moves with every answer, and combining the two predicts your odds before you tap. Once enough responses land after launch, we publish the observed-vs-predicted fit right here — measured, not cherry-picked.
Every factual claim in every card is extracted, web-searched against a per-track allowlist, and entailment-checked against the retrieved passages. Cards on time-sensitive topics (LLM tooling, library APIs) re-validate on a weekly cron.
We show our work: every verified claim cites the page — and the base domain — we checked it against, so you can see exactly what backs a card. Site owners: if you'd prefer we not use or cite your site, email sources@eigencards.com and we'll remove it from our approved sources.
Every card has a one-tap flag in the app — wrong answer, ambiguous, out of date, too easy, too hard, typo. Streaming rules quarantine a card the moment it crosses a threshold, and the loop is built to reissue or retire it within a day.
A flag never hides a card on its own — it queues the card for that night's review. Once a day, a single capped batch re-reviews the most-flagged cards; only a failed review retires one. So neither flag-spam nor a flood of bogus flags can bury good content or run up the bill. Here's exactly how the nightly pass works — the live numbers publish here once it's running after launch.
We don't promise what we haven't written. Here's what's queued for the next pack cuts — ordered by demand × coverage gap × low maturity.
Recall-level cards are free, in every domain, forever. Pro unlocks the harder levels and EigenArena — head-to-head ranked matches where your EigenScore moves against real opponents. New accounts get the full Pro experience free for 7 days.
Every card in your queue passed every gate on this page. New accounts get 7 days of Pro free — keep it or stay on the free Recall tier forever.
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