Dual N-Back - Brain Trainer

Practice Dual N-Back at your own pace, starting with one minute.

Dual N-Back asks you to decide whether the current cue matches the one presented N steps earlier. Practice comparing positions and audio cues, then review your session results over time.

GET STARTED WITH AN INTERACTIVE TUTORIAL
Learn the rules and response controls by trying them before you train.

BUILD A DAILY ROUTINE
Choose 1–5 minutes on Home. The first selection is one minute, and your previous choice is remembered for next time. This is an approximate cue duration; preparation and pauses are additional. Sessions with configurable trial counts and settings are also available.

CHOOSE YOUR N LEVEL
Let the app adjust your N level using the average of your latest three completed sessions under matching conditions, or select it manually. Customize the accuracy thresholds for raising and lowering N in 5-point steps, and reset them to the standard 80% / 50% values at any time. The comparison matches N level, duration, element combination, game mode, cue mode, timing and other training conditions.

REVIEW YOUR PROGRESS
Check your history, practice streak and achievements. The growth report compares only records with the same N level, element combination, game mode, cue mode, timing and other training conditions. View session counts, average, best and a chart for 7 days, 30 days or all saved records.

STANDARD AND EXPANDED MODES
Standard mode, with position and letter cues, is free. The separate Expanded Mode purchase lets you choose any two elements (6 combinations), any three (4 combinations), or all four from position, letter, color and shape. Choose an element count and combination from a clear list; only your selected elements are trained and scored. Existing Expanded Mode owners do not need another purchase.

ADS AND OPTIONAL PURCHASES
If you have not purchased Ad-Free, a banner may appear at the bottom of the result screen. Ads are not shown during training.

Two independent one-time purchases are available. Neither is a subscription:
- Ad-Free removes result-screen ads. It does not include Expanded Mode.
- Expanded Mode unlocks two- to four-element combinations that include color or shape. It does not remove ads.

Current prices appear on the purchase screen. Use Restore Purchases on that screen to check previously purchased entitlements.

DATA AND PRIVACY
Play history, settings and achievements are stored on your device. Usage analytics is off by default. Firebase Analytics is used only when enabled in Settings on the App Store version. Advertising services, including Google Mobile Ads, also make network connections. See App Privacy on the App Store and the privacy policy for details about data handling and purposes.

LANGUAGES
Japanese and English.

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

Privacy policy
https://hori2-t.github.io/dual-nback-legal/privacy.html