# memoryOS vs Kinnu

The clearest difference is ratings volume: memoryOS at 16K against Kinnu's 494. memoryOS also leads on chart position (#47 vs unranked) and iOS requirement (15.2 vs 17.0). Kinnu's advantage is update cadence (every 6 days vs every 3 weeks). On price, rating, review sentiment and ads there is nothing between them.

Both are free to download. memoryOS sells 20 in-app purchases, starting at $3.99 per 7 days and Kinnu sells 4 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.9 for memoryOS against 4.8 for Kinnu. That said, the two scores are not equally well evidenced: memoryOS has 16K ratings behind it against 494, so its average is the more settled of the two. Written reviews are what separate them: 80% of memoryOS's written reviews are positive against 87% of Kinnu's.

memoryOS ships an update every 3 weeks, Kinnu every 6 days. The most recent releases landed on September 25, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | memoryOS | Kinnu |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.9 (16K ratings)](https://appshunter.io/ios/app/memoryos-memory-games/id1553283646/reviews)** | [4.8 (494 ratings)](https://appshunter.io/ios/app/kinnu-general-knowledge/id1625333066/reviews) |
| Number of ratings | **16K** | 494 |
| Positive reviews | 80.4% of reviews | **87.3% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 6 days** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | **#47** | — |
| Size | 248 MB | 101 MB |
| Requires iOS | **15.2** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 12+ |
| Developer | [Encoder Inc.](https://appshunter.io/developer/1524669695) | [Kinnu Limited](https://appshunter.io/developer/1625333068) |

## What reviewers say

### memoryOS

[App page](https://appshunter.io/ios/app/memoryos-memory-games/id1553283646)

**Currently charting:** #47 Top Grossing · Education, #117 Top Free · Education (US App Store)

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:** Vision Pro support

**In-app purchases (20)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Student Weekly Plan | $3.99 | per 7 days |
| Student Monthly Plan | $4.99 | per month |
| Expert Weekly Plan | $6.99 | per 7 days |
| Essential Weekly Plan | $6.99 | per 7 days |
| Essential Monthly Plan | $14.99 | per month |
| Essential Monthly Plan | $14.99 | per month |
| Student 3 Months Plan | $19.99 | per 3 months |
| Expert Monthly Plan | $24.99 | per month |
| Expert 3 Months Plan | $49.99 | per 3 months |
| Expert 3 Months Plan | $69.99 | per 3 months |
| Expert 6 Months Plan | $89.99 | per 6 months |
| Essential Annual Plan | $89.99 | per year |
| Essential Annual Plan | $89.99 | per year |
| Essential Annual Plan | $89.99 | per year |
| Expert Annual Plan | $148.99 | per year |
| Expert Annual Plan | $149.99 | per year |
| Expert Annual Plan | $149.99 | per year |
| 10 Hearts | $0.99 | one-time |
| 10 Loci Coins | $2.99 | one-time |
| 50 Loci Coins | $14.99 | one-time |

**What reviewers like**

- 🚀 Effective memory techniques
- 👍 Interactive and engaging
- 💡 Innovative use of memory palaces
- 🤩 Impressive results in a short time
- 🎉 Fun and enjoyable to use

**What reviewers complain about**

- 💰 Expensive subscription model
- 🐛 Buggy and crashes frequently
- 🤔 Confusing navigation and UI
- 🔒 Lack of transparency around pricing
- 🙄 Aggressive upselling and marketing tactics

**Reported bugs**

- 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**

- 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


### Kinnu

[App page](https://appshunter.io/ios/app/kinnu-general-knowledge/id1625333066)

This app offers bite-sized learning content across a wide range of subjects, from psychology and science to history and technology. It utilizes cognitive science and a unique "Memory Shield" technology to help users retain information effectively, making learning engaging and fun.

**Highlights:** Bite-sized, expert-edited content, Memory Shield technology for retention, Gamified learning sessions, Community-driven content development, Knowledge Bank progress tracking, Interactive, adaptive questions, Audio versions of content

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $1.99 | per month |
| Kinnu Certificate | $7.99 | one-time |
| Kinnu Certificate | $14.99 | one-time |
| Kinnu Certificate | $19.99 | one-time |

**What reviewers like**

- 👍 Engaging learning experience
- 🚀 Efficient micro-learning format
- 🔒 No ads or subscriptions
- 💡 Wide range of interesting topics
- 👍 Gamified learning approach

**What reviewers complain about**

- 🐛 Occasional bugs and crashes
- 🐛 Syncing and progress issues
- 🐛 Inaccurate or incomplete information
- 🐛 AI-generated content quality concerns
- 🐛 Inability to contact developers

**Reported bugs**

- Frequent app crashes
- Progress and data loss issues
- Syncing problems
- Compatibility issues with older devices

**Requested features**

- Ability to highlight or take notes
- More in-depth content and sources
- Customization options (e.g., dark mode)
- Ability to connect with others
- Improved notification and reminder system


## Frequently asked questions

### Is memoryOS free?

memoryOS is free to download, with in-app purchases available.

### Is Kinnu free?

Kinnu is free to download, with in-app purchases available.

### Which has better reviews, memoryOS or Kinnu?

memoryOS is rated higher. memoryOS averages 4.9 out of 5 from 16K ratings, while Kinnu averages 4.8 from 494 ratings.

### Do memoryOS or Kinnu have ads?

Neither memoryOS nor Kinnu shows ads.

### Which is updated more often, memoryOS or Kinnu?

memoryOS ships an update every 3 weeks, and Kinnu every 6 days. Most recently, memoryOS was updated on September 25, 2026 and Kinnu on September 22, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*