Dual N-Back - 脳トレ

Enhanced stats view: now you can track daily progress with N-level trend and accuracy graphs. Feel your 5-minute Dual N-Back habit improving with clear numbers.

⏺ Train working memory in 5 minutes a day. Make brain maintenance a habit, like brushing your teeth.

Dual N-Back is a science-based working memory trainer based on Susanne Jaeggi's 2008 paper "Improving fluid intelligence with training on working memory" — optimized for stress-free daily use on iPhone.

■ Built for you if

• You feel your focus has been slipping
• You want to maintain memory as you age
• You've quit other brain trainers (too hard / too gimmicky / didn't stick)
• You want a 70-second session that fits in any pocket of time
• You prefer quiet consistency over flashy gamification

■ Key Features

【Science-Based Training】 The Dual N-Back task — comparing visual position and audio cues simultaneously to N positions ago — is one of the most-studied paradigms in cognitive training (100+ peer-reviewed papers). This app implements the original task faithfully.

【Around 70 Seconds Per Session】 20 trials × 3.5 seconds, finishable on the train, at lunch, or before bed. We don't recommend long sessions — once daily is enough for measurable effect.

【Auto-Adjusting N Level】 The N level (2-9) auto-tunes based on your last 3 sessions' scores. The AI keeps you at "just above your limit" — sustainable challenge for the long haul.

【3 Game Modes】

• Focus: Standard 20-trial session
• Challenge: Maximize consecutive correct answers
• Endless: No time limit, full immersion

【19 Achievement Badges】 "First Play", "7-Day Streak", "Reach N=5", "90% Accuracy" and more. Badges naturally surface progress without nagging push notifications.

【Privacy First】 All scores and history stay on your device. No server transmission, no tracking. Fully Apple Tracking Transparency compliant.

■ About Ads

The free version includes a modest banner ad. Upgrade to Premium (one-time purchase) to remove all ads.

■ Optional In-App Purchase

"Ad-Free" is a one-time $1.99 purchase. Not a subscription, no renewal forgetting. The free version is fully functional.

■ Devices

iPhone (iOS 17+)

■ Languages

Japanese, English

■ Privacy Policy / Terms

https://hori2-t.github.io/dual-nback-legal/

■ Contact

Feedback and bug reports welcome via App Store reviews or GitHub Issues.