Spaced repetition
LeitnerBox
LeitnerBox schedules every card at the houses that matter — 1, 3, 10, 24 and 54 — so you review the difficult ones often and the settled ones rarely.
Spaced repetition
Cards advance a house when remembered and return to the first when forgotten.
Detailed statistics
House distribution, score by tag and creation activity, charted per box.
Smart tagging
Box-local tags let you build a targeted session out of one topic.