Spaced repetition, without the setup
You forget things on a curve — steep at first, flatter each time you successfully recall. Spaced repetition schedules each review for right around the point you'd start to forget, which is when recalling does the most good.
How Smara schedules cards
Every card gets graded from 1 to 4 after you answer it: Again, Hard, Good, Easy. The interval preview on each button shows exactly when the card would come back. New cards go through short learning steps (a minute, then ten); graduated cards space out to days, weeks, months. Miss one and it starts its climb again.
The default algorithm is SM-2, the same math Anki built its reputation on: simple, predictable, and easy to reason about. FSRS, the modern fitted alternative, is a setting rather than a migration.
Why FSRS wants your review history
SM-2 applies the same formula to everyone. FSRS goes further by treating memory as something measurable: every review you have ever done is a data point about how fast a given card fades for you, and the algorithm fits a per-card model of stability and difficulty to that record. The published result, replicated across large open review datasets, is the same retention from noticeably fewer reviews, because cards stop coming back earlier than they need to.
This is why switching in Smara does not reset anything. Turning FSRS on replays your actual review log to reconstruct each card's memory state, so a deck you have studied for months carries its history into the new schedule. Turn it off and SM-2 resumes. Either way the grading stays the same four honest levels, so the choice is about math, not workflow.
One queue, not twenty deck options
There are no per-deck scheduling options to tune. The Today page pulls every due card across your decks into one session, leads with what's overdue, and introduces new cards at a sane daily pace. If you set an exam date, the pace rebalances so the deck is actually finished before the exam, not after.
What it costs
Studying is free, unlimited, forever. The review loop is the whole point of the app and it never sits behind the paywall. You pay only if you want the AI to do more generating: flashcards from PDFs, quizzes, and practice exams beyond the free allowance.