How to play

The basic loop

Each game shows a grid of tiles drawn from one tier. Each tile is a single item — a word, a kanji, or a grammar pattern.

• Tap a closed tile to peek. The tile flips open with the reading and meaning.
• Hold a closed tile (~half a second) to mark it known. The tile disappears, a new one slides in.
• Tap an open tile (anywhere away from explicit buttons) to dismiss it.
• Each peek nudges the tile's color: bone → amber → orange → vermilion. Three peeks (full vermilion) and the tile heads to the Challenge Box.
• The progress meter at the top tracks your peek-to-removal ratio. The goal: clear with as few peeks as possible.

On a desktop browser, double-click a tile to mark it known instead of holding — both work.

Why tiles auto-shuffle every 60 seconds

Without shuffling, your brain memorizes "the tile in row 2, column 3 means tomorrow" and stops reading the actual content. You'd remove tiles fast and feel confident, but you'd be learning the grid layout, not Japanese. Shuffling forces real recognition every time. (You can also shuffle on demand.)

Inside the back face

Most of the surface dismisses the tile. Inside, small explicit targets open further context without leaving the loop:

• Speaker icon — plays the item aloud. Example sentences use a pre-recorded, native-like Japanese voice; single Goi words and Kanji readings use your device's built-in Japanese voice. Always available — only your device's mute/volume silences it.
• Tap any content word in an example sentence (subtle dotted brass underline) — its Goi card opens above the current one. Conjugations are handled: 行きます, 行こう, 行ったら, 行けば, 寒くなりました all link to their dictionary form (行く, 寒い…) without you thinking about it. Dismiss the popup and you're back where you were.
• Kanji glyph play button (▶) — animates stroke order in the radical colors.
• Radical chip — opens other kanji in the pool that share that radical.
• 例 Examples button (kanji) — opens up to 5 of the most-frequent Goi compounds containing this kanji, each with furigana, English, and audio.

Voices and sounds

Voices. More than 6,000 example sentences are voiced in a native-like Japanese voice, so listening practice sounds natural rather than robotic. Single Goi words and Kanji readings are spoken by your device's own built-in Japanese voice — for the clearest readings, open your iPhone Settings and switch the System Voice to an enhanced Japanese voice. Tap any speaker icon to play; it's always available.

Sounds. The game also answers with short sound effects, so your ear learns the loop without watching the screen: a soft tone when you tap to peek a tile, a distinct one when you hold to remove it, and a small flourish when you clear a tier. On iPhone these pair with a light haptic tap; on iPad — which has no vibration — the sound is the feedback, so a peek and a remove are still easy to tell apart by ear. Prefer silence? Turn them off under Settings → Play audio (the spoken readings stay).

To hear any of it, take your device off silent. Both the voices and the sound effects follow the iPhone/iPad silent switch and volume — flip silent mode off, turn the volume up, and the whole game comes alive.

Reference sets — Bushu and Kana

部首 · Bushu (214 Kangxi radicals) is for learners who like to study primitives before compounds. Each radical's back face shows its Japanese name, meaning, typical position (左偏 / 右旁 / 上冠…), and the kanji from the main pool that contain it; tapping any of those opens the full Kanji entry. About 128 of the 214 radicals are themselves kanji in our pool, so the cross-reference is dense.

仮名 · Kana is a quick reference for hiragana and katakana — the intermediate audience already reads them, so it's there for spotting dakuten / yōon edge cases, not as a beginner drill.

Marked-known tiles in either reference set don't flow into the Challenge Box. Reference is for browsing, not retrieval practice.

Study mode — for material you don't know yet

The regular loop assumes you're testing what you know. For a tier you're meeting for the first time — say, the first time you sit down with N4 kanji — that loop punishes the encoding phase. Tap the Study button (top of any game page, left of Reset) and the app shifts to a calm-list, no-shuffle, no-pressure browse with a calmer Hanada-blue theme.

Peeks and removes still work for the dopamine of seeing tiles vanish — but nothing flows into the Challenge Box and nothing counts toward the dashboard. While the Save Study mode progress setting is on (the default), each module also remembers what you removed and peeked, so you can switch tiers, switch pillars, come back tomorrow, and resume where you left off.

The Challenge Box

Tiles you peek three times in a regular game are saved to the Challenge Box for spaced-retention practice. Find it in the Home page tile grid; "X due / Y total" tells you when to come back. The view is a vertical list, most-overdue-first.

Two actions, two clear meanings

• Hold = "I knew it." Tile disappears. Interval doubles (1 → 2 → 4 → 8 → 16 → 32 → 64 days). Glow drops one step toward bone.
• Tap = "I didn't know it." Tile flips open so you can read the answer. On dismiss, interval resets to 1 day. Glow rises one step toward vermilion.

An item leaves the Challenge Box for good when its glow reaches bone and its interval reaches 60 days — sustained mastery over roughly 2 months.

Progress and Settings

Tap Progress (the bar-chart icon in the bottom control bar on the Home screen) to see what you've done so far — streak counter, today's activity, lifetime marked-known per pillar, and a coverage matrix across the frequency tiers. Read-only and append-only — nothing here grades you.

The bottom control bar, on every screen, holds your quick switches — symbols only: a back arrow (previous page), Home, day/night, and — where they apply — front-face furigana (ふ), the JLPT lens (級, on the Kanji and Bunpou pages), and grid format (▦, in games), plus Settings and About. On the Home screen it also carries the Progress (bar-chart) button. The Settings page (gear icon) holds the rest: auto-shuffle, sound effects, Study-mode persistence, and daily reminders. If you're signed in to iCloud on your device, your Challenge Box and progress sync automatically between your iPhone and iPad — no account, no server-side login, no setup step.

Tips

• Daily ten to twenty minutes beats weekly hour-long sessions. Recognition compounds with frequency, not session length.
• Trust the exposure. You don't have to memorize on the first peek — the same tile will come back.
• Use the Challenge Box deliberately. When it has 20+ items, work through them before adding more.
• Don't try to "finish" a tier. Tiers refill from the pool. Stop when your attention drops, not when the grid is empty.