# Cardflow+ by Qrayon vs KnowledgeBase Builder

The clearest difference is price: KnowledgeBase Builder at $8.99 against Cardflow+ by Qrayon's $14.99. KnowledgeBase Builder also leads on review sentiment (91% vs 69%) and device support (3 vs 1). Cardflow+ by Qrayon's advantage is ratings volume (1.5K vs 24) and update cadence (every 6 days vs fortnightly). On rating, ads, in-app purchases and monetization model there is nothing between them.

Cardflow+ by Qrayon costs $14.99 and KnowledgeBase Builder $8.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 4.6 for Cardflow+ by Qrayon against 4.7 for KnowledgeBase Builder. That said, the two scores are not equally well evidenced: Cardflow+ by Qrayon has 1.5K ratings behind it against 24, so its average is the more settled of the two. Written reviews are what separate them: 69% of Cardflow+ by Qrayon's written reviews are positive against 91% of KnowledgeBase Builder's.

Cardflow+ by Qrayon ships an update every 6 days, KnowledgeBase Builder fortnightly. The most recent releases landed on September 23, 2026 and September 7, 2026 respectively.

## The numbers

| Metric | Cardflow+ by Qrayon | KnowledgeBase Builder |
| --- | --- | --- |
| Price | $14.99 | **$8.99** |
| Rating | [4.6 (1.5K ratings)](https://appshunter.io/ios/app/cardflow-plus-by-qrayon/id990108843/reviews) | **[4.7 (24 ratings)](https://appshunter.io/ios/app/knowledgebase-builder/id1448579863/reviews)** |
| Number of ratings | **1.5K** | 24 |
| Positive reviews | 69.4% of reviews | **90.9% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 6 days** | Fortnightly |
| Monetization | Paid | Paid |
| Size | 16 MB | 21 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 17+ | 4+ |
| Developer | [Qrayon, LLC](https://appshunter.io/developer/354980265) | [Ingo Straub](https://appshunter.io/developer/1398145160) |

## What reviewers say

### Cardflow+ by Qrayon

[App page](https://appshunter.io/ios/app/cardflow-plus-by-qrayon/id990108843)

This app digitizes the tactile experience of using index cards on an iPad. It allows users to brainstorm, plan projects, and organize ideas with a flexible, freeform layout. Capture thoughts with writing, drawing, or photos, and arrange them on a digital board.

**Highlights:** Digital index card creation, Freeform layout and organization, Inkflow vector ink system, Typing with various fonts, Photo import for backgrounds, Project planning and storyboarding

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 🚀 Smooth and responsive
- 🖋️ Great for handwriting and drawing
- 📚 Useful for organizing thoughts and ideas
- 🎨 Flexible color and formatting options
- 🔗 Ability to link cards

**What reviewers complain about**

- 🐛 Frequent crashes and freezes
- 🖌️ Palm rejection issues when writing
- 🔍 Lack of search/handwriting recognition
- 📁 Limited organizational features (no folders)
- 🔢 Inability to resize or customize card sizes

**Reported bugs**

- Cards randomly losing content
- Exporting issues with images and links
- Inconsistent behavior when flipping cards

**Requested features**

- Add a study/quiz mode for flashcards
- Improve syncing and cloud integration
- Allow multiple images per card
- Provide more customization options for text and formatting
- Implement a highlighter tool separate from the pen


### KnowledgeBase Builder

[App page](https://appshunter.io/ios/app/knowledgebase-builder/id1448579863)

Organize and search text documents and web pages with links within a mind map structure. Automatically create mind maps from text, import Wikipedia articles, and export your knowledge base as HTML. Also functions as a flowcharting tool.

**Highlights:** Save text documents and web pages, Full-text search, Organize with mind maps, Automatic mind map creation, Wikipedia import, Export to HTML, Flowcharting tool

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Cardflow+ by Qrayon free?

Cardflow+ by Qrayon costs $14.99, with no in-app purchases.

### Is KnowledgeBase Builder free?

KnowledgeBase Builder costs $8.99, with no in-app purchases.

### Which has better reviews, Cardflow+ by Qrayon or KnowledgeBase Builder?

KnowledgeBase Builder is rated higher. Cardflow+ by Qrayon averages 4.6 out of 5 from 1.5K ratings, while KnowledgeBase Builder averages 4.7 from 24 ratings.

### Do Cardflow+ by Qrayon or KnowledgeBase Builder have ads?

Neither Cardflow+ by Qrayon nor KnowledgeBase Builder shows ads.

### Which is updated more often, Cardflow+ by Qrayon or KnowledgeBase Builder?

Cardflow+ by Qrayon ships an update every 6 days, and KnowledgeBase Builder fortnightly. Most recently, Cardflow+ by Qrayon was updated on September 23, 2026 and KnowledgeBase Builder on September 7, 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.*