Jangdan Downloads & RevenueJangdan: Korean Rhythm Tap · App Store

Now in English: the game follows your device language (English or Korean), and you can switch anytime in Info. Every rhythm is performed for you before you play, so you learn it by ear.

Gutgeori, Jajinmori, Hwimori, Eotmori. Hear four traditional Korean rhythm cycles (jangdan) in a demo performance, then play them back with one finger. A one-button rhythm game drawn in the feel of ink and hanji paper.

■ How a round goes
· Pick a rhythm — start with Gutgeori; clearing one opens the next.
· Demo — a spirit circles the orbit at real play speed and performs the rhythm. Sounding notes jump in gold, and the spoken drum syllable (deong, gi, deok, kung …) appears large in the center. You can skip it.
· One count-in cycle with a guide beat — then it's your turn.
· Play — tap anywhere the moment the orbiting spirit touches a note. Judgements are Perfect, Good and Miss.
· Result — survive to the end with 85% accuracy or better to clear. You get a grade on the traditional five-step scale (su, u, mi, yang, ga), with Perfect / Good / Miss / stray-tap counts and your best combo.

■ Four rhythms
· Gutgeori — deong — gideok — kung — deoreoreoreo. A long rest, then a quick roll.
· Jajinmori — deong deong deong tta kung tta. Even steps that split finely at the end.
· Hwimori — deong kung tta kung tta tta. A little faster every cycle.
· Eotmori — deong gideok — kung deok deoreo. A 3+2+3+2 mixed meter: long and short beats alternate, and the orbit draws long beats wide and short beats narrow.
Each rhythm's syllable pattern is simplified for play.

■ Stamina and accuracy
You have 8 stamina. Each missed note costs 1, every two stray taps cost 1, and the round ends when it runs out. Timing windows differ by rhythm; Gutgeori is the most forgiving. When you fail a rhythm, the demo plays again on your next try.

■ Tap calibration
Latency for the built-in speaker and wired earphones is corrected automatically. With Bluetooth earphones, open Tap calibration on the title screen first and tap eight times along with the guide beat. The result screen also measures how early or late your taps were on average and offers a correction when they lean one way.

■ Sound and haptics
All sound is synthesized live on the device; no recorded instrument samples are used. Every judgement comes with haptics (firm for Perfect, soft for Good). Sound and vibration can be turned off separately at the top right of the title screen. With the iPhone silent switch on, there is no sound.

■ Resume
If you leave mid-performance, progress is saved on the device, and Resume on the title screen brings you back to the same spot with a countdown (not during the demo or count-in; one saved round).

■ Price and connection
· Free to start. Gutgeori and Jajinmori are free; the one-time Full Unlock purchase opens Hwimori and Eotmori. No ads, no subscriptions.
· If you bought the app before it became free, everything is unlocked automatically.
· Works entirely on the device — no internet connection, account or l