memoryOS vs VisualGrammar
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
memoryOS
Enhance your memory with interactive lessons and a 3D virtual mind palace game. This app uses scientifically proven techniques like spaced repetition to boost long-term memory storage and knowledge retention. It's designed to make memorization skills joyful and effective for everyone.
- Interactive memory lessons
- 3D Virtual Mind Palaces
- Spaced repetition system
- Gamified learning
- Memorize names, lists, numbers, and more
- Advanced study techniques
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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
VisualGrammar
This app uses an AI-powered model inspired by Reed–Kellogg diagrams to automatically generate visual representations of sentence structure. It works offline, making grammar analysis accessible and engaging for students and language enthusiasts.
- Automatic sentence diagram generation
- Offline functionality
- Lightweight AI model
- Visualizes grammar
- Privacy-first design
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Transform how you understand and analyze sentences with our innovative app, powered by a lightweight AI model inspired by the legacy of Reed–Kellogg—a pioneering system that revolutionized sentence diagramming. No internet needed! Simply input any sentence, and watch as the app automatically generates a beautifully structured diagram, revealing the intricate relationships between words, phrases, and clauses.This AI-powered diagram generator eliminates the need for manual branding tools. Our intelligent agent automatically creates professional diagrams with embedded branding elements directly from your input. No additional tools or manual steps required - simply type your English Sentence and let AI handle the rest. Key Features: Offline Functionality: Works seamlessly without an internet connection, perfect for classrooms, travel, or remote learning. Lightweight AI Model: Efficiently diagrams sentences on-device, with ongoing accuracy improvements through advanced syntax parsing. Educational & Fun: Ideal for students, teachers, and language enthusiasts to visualize grammar in action—bridging the gap between traditional diagrams and modern AI. Limitations: Designed for simplicity; very complex sentences (e.g., nested clauses or rare syntactic structures) may require future enhancements. Why It Stands Out: The Art of Language: Every sentence is a masterpiece of structure and meaning. Our app brings this artistry to life, helping you see the hidden patterns and rhythms of grammar. Privacy-First: Offline operation ensures your data stays secure, with no reliance on cloud processing. Accessible Learning: Turn the poetry of syntax into a visual experience, making language analysis intuitive and engaging for all. Whether you’re mastering grammar, teaching in the classroom, or exploring the beauty of syntax, this app turns language into a visual masterpiece.
Screenshots
Verdict
The clearest difference is review sentiment: memoryOS at 80% against VisualGrammar's 0%. memoryOS also leads on price (Free vs $3.99) and rating (4.9 vs 3.5). VisualGrammar's advantage is in-app purchases (none vs 10). 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
memoryOS is free to download; VisualGrammar costs $3.99 up front. memoryOS sells 9 in-app purchases, starting at $5.99 per month. VisualGrammar asks for nothing beyond the download.
memoryOS holds the better App Store score, 4.9 against 3.5. 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 VisualGrammar's.
memoryOS ships an update fortnightly, VisualGrammar every 10 days. The most recent releases landed on November 11, 2026 and November 7, 2026 respectively.
| Parameter | memoryOS | VisualGrammar |
|---|---|---|
| Price | Free — better | $3.99 |
| Rating | 4.9 (17K ratings) — better | 3.5 (2 ratings) |
| Positive reviews | 80.2% of reviews — better | 0.0% of reviews |
| Number of ratings | 17K — better | 2 |
| Update frequency | Fortnightly | Every 10 days — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases — better | Paid |
| Best chart rank | #55 — better | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 15.2 — better | 17.6 |
| Further details — not scored | ||
| Size | 232 MB | 16 MB |
| Age rating | 4+ | 4+ |
| Developer | Encoder Inc. | Simin Dai |
Customer experience
memoryOS
VisualGrammar
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
VisualGrammar
Not enough reviews yet to summarise bugs or requests.
In-app purchases
memoryOS
- Student Monthly Plan7 Days trial$5.991 Month
- Essential Weekly Plan7 Days trial$6.997 Days
- Essential Monthly Plan$15.991 Month
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- Expert Monthly Plan$27.991 Month
- Essential Annual Plan7 Days trial2 variants$89.991 Year
- Expert Annual Plan7 Days trial$148.991 Year
- Expert Annual Plan1 Month trial$149.991 Year
- Expert Annual Plan7 Days trial$159.991 Year
- Expert Annual Plan1 Month trial$159.991 Year
VisualGrammar
No in-app purchases









