iAddThree vs Dual N
Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.
iAddThree
Engage your mind with a unique math game that challenges your focus and cognitive abilities. The objective is to add three to each number presented, with a special rule where numbers wrap around to zero instead of forming double digits. This simple yet effective exercise provides a mental workout.
- Cognitive training
- Focus improvement
- Unique math rules
- Brain exercise
- High score challenges
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Train your brain and improve your focus with the simple yet challenging math game, iAddThree. Adapted from an exercise that was used to measure cognitive focus in the popular book Thinking Fast and Slow by Daniel Kahneman, iAddThree engages your mind by bending the rules of basic math to give your brain the mental exercise it deserves. THE RULES------------- It's simple. Just add 3 to each of the four numbers that are presented. The challenge? No double digits. Instead, you must wrap around to 0. Normally, 8+3=11, but in iAddThree, 8+3=1. Think of it as a line of numbers that are constantly repeating. 8 -> 9 -> 0 -> 1 -> 2 -> 3. The struggle provided by this simple math game will have you boasting about your high score to all your friends. So, how well do you think you can iAddThree?
Dual N
This app is a brain game designed to improve working memory and cognitive skills through a challenging memory-training exercise. It offers customizable difficulty, goal setting, and global leaderboards to track progress. An ad-free experience is available via a subscription.
- Working memory training
- Customizable difficulty (N-value, interval, session length)
- Goal setting and reminders
- Global leaderboards
- Multilingual support
- Ad-free Pro version
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Dual NBack – Brain Training to Improve Memory Dual NBack is a fun and challenging brain game designed to strengthen your working memory. Set goals, get reminders, and climb the global leaderboards as you sharpen your mind! What Is Dual NBack? Dual NBack is a memory-training game that presents audio (letters) and visual (positions) sequences simultaneously. Research suggests that consistent play may enhance your working memory—the ability to hold and process information briefly—and also boost short-term recall. How to Play The game starts at Level N=2, where you need to remember the position (square) and the sound (letter) from two turns back. If the current position or sound matches what was shown two turns ago, tap the corresponding button. Strong performance automatically raises your level, but you can manually adjust the difficulty whenever you like. Key Features Customizable Settings Tailor your training: tweak the N-value (number of turns to recall), the interval between sounds/blocks, and session length as you see fit. Reminders & Goals Set daily or weekly targets and enable notifications to help you practice consistently. Global Leaderboards Compare your scores with players worldwide and see how you rank as you improve. Share Function Post your results on social media or messaging apps to challenge your friends and family. Multilingual Support Currently offered in English and Japanese, with more languages on the way. Why Train Your Working Memory? Working memory stores information for a few seconds to minutes, enabling you to make decisions, perform calculations, or tackle other cognitive tasks. Playing Dual NBack regularly can help strengthen this mental capacity, potentially improving focus, concentration, and overall brain agility. Ad-Free Experience with Dual NBack Pro Enjoy a 3-day free trial of Dual NBack Pro to train with no ads or interruptions. If you choose to purchase Dual NBack Pro, the payment is charged to your iTunes account. Renewal fees are charged within 24 hours before the current subscription period ends. You can cancel your subscription anytime: Go to Settings → tap your name → Subscriptions → locate and cancel the subscription you want to end. If you don’t cancel before the trial ends, the paid subscription automatically starts. Privacy Policy: https://goukakuappli.co.jp/privacy End User License Agreement (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Summary Strengthen Your Mind: Give your working memory a proven workout. Adapt the Difficulty: Start at N=2 or set your preferred challenge level. Stay Motivated: Leverage reminders, goals, and leaderboards to keep pushing your limits. Go Pro for No Ads: Take advantage of a 3-day free trial and upgrade to an ad-free training experience. Download Dual NBack now and take your cognitive performance to a new level!
Screenshots
Verdict
The clearest difference is review sentiment: iAddThree at 100% against Dual N's 51%. iAddThree also leads on rating (5.0 vs 4.6). Dual N's advantage is ratings volume (376 vs 1) and iOS requirement (15.0 vs 17.0). On price, update cadence, ads and in-app purchases there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. iAddThree sells 1 one-off in-app purchase and Dual N sells 2 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.
iAddThree holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: Dual N has 376 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 100% of iAddThree's written reviews are positive against 51% of Dual N's.
iAddThree ships an update every 3 weeks, Dual N fortnightly. The most recent releases landed on October 14, 2026 and October 27, 2026 respectively.
| Parameter | iAddThree | Dual N |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) — better | 4.6 (376 ratings) |
| Positive reviews | 100.0% of reviews — better | 50.9% of reviews |
| Number of ratings | 1 | 376 — better |
| Update frequency | Every 3 weeks | Fortnightly — better |
| Ads | Yes | Yes |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 30 MB | 199 MB |
| Age rating | 4+ | 4+ |
| Developer | Nikolai Nobadi | GOKAKU SUPPLI, LIMITED LIABILITY CO. |
Customer experience
iAddThree
Dual N
In-app purchases
iAddThree
- Remove Ads$0.99
Dual N
- NBack Monthly Subscription3 Days trial$0.991 Month
- Lifetime Pass$12.99
Questions
Is iAddThree free?
Is Dual N free?
Which has better reviews, iAddThree or Dual N?
Do iAddThree or Dual N have ads?
Which is updated more often, iAddThree or Dual N?
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