Chinese,
fine tuned
to your brain.
TongTong assesses your Mandarin from your very first session, then builds a personalised path that pushes the edge of what your memory can actually hold. No vocabulary import. No grinding from zero. Start exactly where you left off.
A proprietary engine
picks every card.
Every time you answer, TongTong's intelligent picker weighs everything you could see next — due reviews, spot-checks, fresh words at your edge — and scores each candidate across 30 dimensions of your memory. The single best card wins. Thousands of tiny decisions, all of them about you.
- 01Tuned to your 85% sweet spot.Scoring peaks where you have an 85% chance of success — the difficulty where memory grows fastest. Never trivial, never crushing.
- 02It measures what actually stuck.Hours after every card, the engine checks whether the knowledge survived — and learns from durable gains, not lucky streaks.
- 03Hard guarantees underneath.Missed words return at picks 3, 8 and 20. Overdue reviews get rescued. Words you add yourself always come first.
Comprehensible input.
Slightly beyond your edge.
Stephen Krashen's “i+1” hypothesis: learners acquire language best when they understand conversations slightly beyond their current proficiency. TongTong picks stories that match your level today, close enough to follow, just hard enough to grow.
Synced transcripts, level-tagged episodes, native-speaker narration. New episodes added every week.
All relevant vocabulary.
Ranked by what matters.
Most apps stop at HSK 6. TongTong studies the full 40,000+ word corpus. Every word a fluent speaker meets in real life. Continuously refined with modern conversational analysis so you learn the most useful, most frequent words first, and never waste a session on archaic vocabulary.
Your ability,
refined with every answer.
Most apps reduce you to a streak. TongTong models your ability as one continuous estimate, fusing three established sciences into a single picture of how you learn, and where you'll grow next.
Spaced Repetition
Each word lives on its own forgetting curve. TongTong returns it the moment your memory is about to slip, not a day too early, not a day too late.
Psychometrics
The science behind standardized tests, adapted for Chinese. Every answer estimates your ability against the entire vocabulary, not just the words you have seen.
Probabilities
A probabilistic model continuously infers what you know. Confidence rises, uncertainty narrows, the next card is always the one that teaches us most about you.
Your next review
is due.
Free. No subscription, no ads, no notifications hunting your dopamine. The same algorithm that ranks 40,000+ words is yours from the first card.