Comparison

memoryOS vs Master Any Stack

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

memoryOS

Enhance your memory and focus with interactive lessons and a virtual mind palace game. Learn scientifically proven techniques to improve knowledge retention and recall a wide range of information, from names and numbers to complex data and entire books.

Highlights
  • Interactive bite-sized lessons
  • Virtual Mind Palaces game
  • Spaced repetition system
  • Scientifically proven techniques
  • Improve knowledge retention
  • Memorize diverse information
Features
Read full description

memoryOS contains interactive bite-sized lessons by a 2X World Memory Champion and an educational 3D game of Virtual Mind Palaces - all in one easy-to-use app. It utilizes scientifically proven memory techniques, spaced repetition and patented game mechanics to enhance long-term memory storage and improve knowledge retention. memoryOS is loved by 500,000+ people worldwide because it is a whole new, joyful & game-changing tool for obtaining the most effective memorization skills. Co-founded by Jonas von Essen, who went from struggling to remember to becoming a World Memory Champion, winning on Who Wants To Be a Millionaire, "Jeopardy, and setting a world record by memorizing 100,000 decimals of Pi . memoryOS app has over 18k public worldwide ratings on Apple and Google app stores combined, averaging 4.8 stars. Users also continue adding 5-star reviews daily, sharing how effective and life-changing memoryOS has been for them. Also, memoryOS remains the most crowdfunded app in Kickstarter’s history. Memorization is as important as reading and writing and should be taught as our base skill. Our mission is to enable millions of people to remember needed information easily. With memoryOS, you will learn how to memorize: - Names, Long speeches, Lists of items, Birthdays, Personal facts, Passwords, Trivia, Languages, Vocabulary and phrases, Countries and Capitals, Flags, Historical timeline, Numbers, Periodic table - Content of complete books, Dates of significant events, Complex data structures, Concepts, and figures - Art, Anatomy, Decks of cards, Advanced number systems; Long sequences of numbers, Binary Digits You will also learn: - How to keep track of years, months, weeks, and days - Advanced study techniques, Spaced Repetition system, Speed memorization Why did Google Brands Accelerator recognize memoryOS as being 'Light Years Ahead' in the memory space? • memoryOS delivers results: During our pre-launch phase, thousands of users completed our demo and, on average, had a 70% increase in recall and a 60% increase in recall speed just after the first ~40min session. • Providing your mind with structured storage space: We have spent tens of thousands of hours creating and optimizing our Virtual Mind Palaces, so you don’t have to spend months constructing your own the hard way. These virtual palaces serve as blueprints for your mind's storage space, allowing you to easily encode, store and recall like a memory champion. • A proven innovative approach that works: During our research and development stage, thousands of people of all age groups and even those with difficult medical conditions found memoryOS as an effective and useful tool. Actual results exceeded our team’s expectations. • Gamified edtech at its best: memoryOS has proven to work on people with no prior gaming experience - anyone can use it. Utilizing the power of the Unity game engine, memoryOS is widely accessible on all mobile and tablet devices and is soon coming to VR. -- Joining memoryOS is free. This provides extensive value on the free plan, and you are not obligated to pay to start using it. You can subscribe to a Student Premium plan for as low as $3.49/month when billed annually or $4.99/month when billed monthly (it can be 10-20% higher in some countries due to local taxes). You can subscribe through the 'Shop' section of the memoryOS app and find the above-mentioned or go to your App Store app's profile and choose a desired plan there. Recurring payments will automatically renew unless you cancel your account at least 24 hours before the end of the current subscription period. You can manage your subscription, cancel anytime, or turn off auto-renewal by accessing your iTunes account. Join the memoryOS community of over 500,000+ early adopters who share this memorable journey! -- Terms: memoryOS.com/terms Privacy policy: memoryOS.com/privacy-policy Learn more at: memoryOS.com Contact us: support@memoryOS.com

About

Master Any Stack

Learn to memorize the order of a deck of cards with this user-friendly app. It offers video and text training on a unique memorization method, allows customization of stacks, and provides various practice modes to help you master card sequences.

Highlights
  • Learn memorization method via video and text
  • Create and practice custom card stacks
  • Practice specific sections of the deck
  • Utilize P.A.O. (Person, Action, Object) method
  • Timed and free play practice modes
  • Track daily practice streaks
Features
Read full description

‘Master Any Stack’ is the best, fastest and most user friendly way to memorize the order of a deck of cards. Create your own stacks or learn a pre-programmed one (such as mnemonica), learn our original method for memorization and game your way to stack mastery with our addicting practice settings. We’ve been teaching the memorized deck for YEARS and this app is the ultimate evolution of our knowledge, making your journey as seamless and enjoyable as possible. ‘Learn the Method’ Under this tab you’ll find video and text training all about our method for learning the stack. This knowledge is so sought after - 100’s of customers have paid $97 for it in the past. ‘Customize Your Stack’ So many people begin their journey to learning stack by asking a completely useless question: “Which stack?” We say: you can learn them all. Under this tab you’ll be able to pick a stack to practice, as well as add your own CUSTOM stacks. Essentially you can learn an infinite number of stacks with this app, or stick with those we’ve pre-programmed. (pre-programmed ft. Mnemonica, Aronoson, Sti-stebbins) ‘Practice P.A.O’ Our method for learning the stack uses the unique P.A.O Method (person, action, object.) You will be able to enter your own custom values and practice them within the app! In order to protect the integrity of our methods we won’t go any deeper into that here, but you will be able to practice P.A.O within the app. ‘Practice the Stack’ This is where you’ll spend most of your time. In the ‘practice the stack’ part of the app there are a lot of settings you can play around with! You can practice any part of the stack e.g. 1-10, 5-25, or 1-52 (anything you choose!) You can also practice based on suits, odd cards, even cards, red or black cards and more! You can also set your own rules for the training deciding whether you want to be timed, lose lives, or practice in free play mode. Your custom stacks also automatically sync with this part of the app. Each day you practice you’ll update your streak - get to thirty days and we’ll send you something special! This app is constantly being worked on to make it the best app in the magic industry regarding stack training - you won’t be disappointed. Buy now!

Screenshots

memoryOS4 screens
Master Any Stack4 screens

Verdict

The call

The clearest difference is price: memoryOS at Free against Master Any Stack's $14.99. memoryOS also leads on rating (4.9 vs 3.0) and ratings volume (16K vs 4). Master Any Stack's advantage is in-app purchases (none vs 28) and iOS requirement (13.0 vs 15.2). On update cadence, ads and device support 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

CostPrice · In-app purchases · Ads · Monetization

memoryOS is free to download; Master Any Stack costs $14.99 up front. memoryOS sells 20 in-app purchases, starting at $3.99 per 7 days. Master Any Stack asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

memoryOS holds the better App Store score, 4.9 against 3.0. That said, the two scores are not equally well evidenced: memoryOS has 16K ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 80% of memoryOS's written reviews are positive against 67% of Master Any Stack's.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 weeks. The most recent releases landed on October 3, 2026 and September 20, 2026 respectively.

Scorecard8 real differences · 3 level
memoryOS versus Master Any Stack: the parameters behind the verdict, then further details
ParametermemoryOSMaster Any Stack
PriceFree — better$14.99
Rating4.9 (16K ratings) — better3.0 (4 ratings)
Positive reviews80.5% of reviews — better66.7% of reviews
Number of ratings16K — better4
Update frequencyEvery 3 weeksEvery 3 weeks
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
Best chart rank#50 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.213.0 — better
Further details — not scored
Size248 MB22 MB
Age rating4+4+
DeveloperEncoder Inc.The Daily Magician Ltd.

Customer experience

memoryOS

All ratings16,469 ratings
Positive97.2%
Neutral1.0%
Negative1.8%
Written reviews1,653 reviews
Positive80.5%
Neutral4.9%
Negative14.6%

Master Any Stack

All ratings4 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews3 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

Bugs and requests

memoryOS

Reported bugs

5 issues
  • Login issues and account management problems
  • Frequent crashes and app instability
  • Navigation and UI elements not working as expected
  • Syncing issues between devices and lost progress
  • Connectivity problems when using cellular data

Requested features

5 requests
  • More free content and lessons
  • Ability to create custom memory palaces
  • Better progress tracking and analytics
  • Integration with other learning/productivity apps
  • Offline mode for lessons and memory palaces

Master Any Stack

Not enough reviews yet to summarise bugs or requests.

In-app purchases

20 purchases

memoryOS

Subscriptions17
  • Student Weekly Plan$3.997 Days
  • Student Monthly Plan7 Days trial$4.991 Month
  • Expert Weekly Plan7 Days trial$6.997 Days
Show 14 more
  • Essential Weekly Plan7 Days trial$6.997 Days
  • Essential Monthly Plan3 variants$14.991 Month
  • Essential Monthly Plan7 Days trial$14.991 Month
  • Student 3 Months Plan$19.993 Months
  • Expert Monthly Plan2 variants$24.991 Month
  • Expert 3 Months Plan7 Days trial$49.993 Months
  • Expert 3 Months Plan$69.993 Months
  • Expert 6 Months Plan7 Days trial$89.996 Months
  • Essential Annual Plan1 Month trial$89.991 Year
  • Essential Annual Plan7 Days trial3 variants$89.991 Year
  • Essential Annual Plan14 Days trial$89.991 Year
  • Expert Annual Plan7 Days trial$148.991 Year
  • Expert Annual Plan7 Days trial$149.991 Year
  • Expert Annual Plan1 Month trial2 variants$149.991 Year
One-time3
  • 10 Hearts$0.99
  • 10 Loci Coins$2.99
  • 50 Loci Coins$14.99
None

Master Any Stack

No in-app purchases

Questions

Is memoryOS free?
memoryOS is free to download, with in-app purchases available.
Is Master Any Stack free?
Master Any Stack costs $14.99, with no in-app purchases.
Which has better reviews, memoryOS or Master Any Stack?
memoryOS is rated higher. memoryOS averages 4.9 out of 5 from 16K ratings, while Master Any Stack averages 3.0 from 4 ratings.
Do memoryOS or Master Any Stack have ads?
Neither memoryOS nor Master Any Stack shows ads.
Which is updated more often, memoryOS or Master Any Stack?
memoryOS ships an update every 3 weeks, and Master Any Stack every 3 weeks. Most recently, memoryOS was updated on October 3, 2026 and Master Any Stack on September 20, 2026.

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