memoryOS vs Proportion_Calculator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- Interactive bite-sized lessons
- Virtual Mind Palaces game
- Spaced repetition system
- Scientifically proven techniques
- Improve knowledge retention
- Memorize diverse information
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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
Proportion_Calculator
This app helps you find the unknown value in proportions by showing step-by-step calculations. It's useful for various applications, from cooking to science, and offers a simple, fast, and visually appealing way to solve proportion problems.
- Solves for unknown values in proportions
- Provides labeled step-by-step explanations
- Fast calculation speed
- User-friendly interface
- Math keyboard for easy input
- Smart, eye-friendly color theme
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Proportion calculator This application is designed to find the “x” or “unknown” value in a proportion of two ratios. It does so while providing the labeled steps that help the user to understand proportions deeply. It also goes by the name solving proportions calculator. To know more about the proportions and this app, keep reading. What are proportions? Proportions show a relation between two different ratios. These ration seem different but are actually related in similar way. Proportions have many uses because if you know one ratio you can find the values of other proportions. It has its application everywhere from baking to higher sciences. Example: The tv cooking shows often provide an ingredient list of 4 to 5 servings. If you want to make more servings then proportion calculator will be useful in finding the quantity of ingredients. Proportion formula: There is no formula to solve proportions. It is just a matter of writing and simplifying. Say there are two ratios (a) 2:3 and (b) 7:x To find the value of x in the second proportion: 1. Write the ratios in fraction form. 2. Cross multiply. 3. Separate the x and solve. This will give the missing value. How to use the proportion solver? The application is easy to operate due to its up-to-the-mark useability. 1. Enter the ratios in the correct order, first goes first. 2. Remember to enter the unknown value as x. 3. Click “Calculate”. Features: You will understand why the claim is that “This is one of the best proportion solvers” once you install and try it. Its main highlights are: 1. It is to the point with no extra buttons and options to complicate things. 2. The answer is calculated very fast so it is time-saving. 3. Smart color theme which is easy on the eyes. 4. Math keyboard for convenient inputting.
Screenshots
Verdict
The clearest difference is review sentiment: memoryOS at 80% against Proportion_Calculator's 0%. memoryOS also leads on rating (4.9 vs 2.0) and update cadence (every 3 weeks vs every 24 months). Proportion_Calculator's advantage is in-app purchases (none vs 28) and iOS requirement (13.0 vs 15.2). On price, 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
Both are free to download. memoryOS sells 23 in-app purchases, starting at $3.99 per 7 days. Proportion_Calculator asks for nothing beyond the download.
memoryOS holds the better App Store score, 4.9 against 2.0. That said, the two scores are not equally well evidenced: memoryOS has 17K ratings behind it against 2, 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 0% of Proportion_Calculator's.
memoryOS ships an update every 3 weeks, Proportion_Calculator every 24 months. The most recent releases landed on October 16, 2026 and September 30, 2026 respectively.
| Parameter | memoryOS | Proportion_Calculator |
|---|---|---|
| Price | Free | Free |
| Rating | 4.9 (17K ratings) — better | 2.0 (2 ratings) |
| Positive reviews | 80.5% of reviews — better | 0.0% of reviews |
| Number of ratings | 17K — better | 2 |
| Update frequency | Every 3 weeks — better | Every 24 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Best chart rank | #58 — better | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 15.2 | 13.0 — better |
| Further details — not scored | ||
| Size | 248 MB | 19 MB |
| Age rating | 4+ | 4+ |
| Developer | Encoder Inc. | Ahmad Sattar |
Customer experience
memoryOS
Proportion_Calculator
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
Proportion_Calculator
Not enough reviews yet to summarise bugs or requests.
In-app purchases
memoryOS
- Student Weekly Plan$3.997 Days
- Student Monthly Plan7 Days trial$5.991 Month
- Expert Weekly Plan7 Days trial$6.997 Days
Show 17 moreShow fewer
- Essential Weekly Plan7 Days trial$6.997 Days
- Essential Monthly Plan7 Days trial$14.991 Month
- Essential Monthly Plan2 variants$14.991 Month
- Essential Monthly Plan$16.991 Month
- Student 3 Months Plan$19.993 Months
- Expert Monthly Plan$24.991 Month
- Expert Monthly Plan$29.991 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 Plan1 Month trial$149.991 Year
- Expert Annual Plan7 Days trial$174.991 Year
- Expert Annual Plan1 Month trial$174.991 Year
- 10 Hearts$0.99
- 10 Loci Coins$2.99
- 50 Loci Coins$14.99
Proportion_Calculator
No in-app purchases
Questions
Is memoryOS free?
Is Proportion_Calculator free?
Which has better reviews, memoryOS or Proportion_Calculator?
Do memoryOS or Proportion_Calculator have ads?
Which is updated more often, memoryOS or Proportion_Calculator?
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