# SideBooks vs きくPDF

The clearest difference is update cadence: きくPDF at every 4 days against SideBooks's every 9 days. SideBooks's advantage is device support (3 vs 1) and iOS requirement (15.0 vs 18.0). On price, ads and in-app purchases there is nothing between them.

Both are free to download. SideBooks sells 1 one-off in-app purchase and きくPDF sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

SideBooks ships an update every 9 days, きくPDF every 4 days. The most recent releases landed on November 8, 2026 and November 1, 2026 respectively.

## The numbers

| Metric | SideBooks | きくPDF |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (98 ratings)](https://appshunter.io/ios/app/sidebooks/id409777225/reviews)** | — |
| Number of ratings | **98** | — |
| Positive reviews | 73.8% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 9 days | **Every 4 days** |
| Monetization | Free with in-app purchases | — |
| Size | 33 MB | 59 MB |
| Requires iOS | **15.0** | 18.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Tatsumi-system Co., Ltd.](https://appshunter.io/developer/409777230) | [Nue K.K.](https://appshunter.io/developer/1892031710) |

## What reviewers say

### SideBooks

[App page](https://appshunter.io/ios/app/sidebooks/id409777225)

This app offers a high-performance PDF and comic viewer with realistic paper-turning animations. It supports various viewing directions, enhanced bookshelf management, and secure password protection for your documents. Easily import files from multiple sources and enjoy a customizable reading experience.

**Highlights:** Realistic paper curl animation, Multiple viewing directions, Enhanced bookshelf management, Password protection, Dropbox and iTunes file import, Supports PDF, ZIP, CBZ, RAR, CBR

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Thema extension Add-On | $0.99 | one-time |

**What reviewers like**

- 🚀 Smooth page turning
- 📚 Great for reading comics and manga
- 🗂️ Excellent folder organization
- 🔍 Useful search and table of contents features
- 💻 Seamless Dropbox integration

**What reviewers complain about**

- 🐛 Crashes when loading large files
- 🚫 Limited file format support (no CBZ/CBR)
- 🔍 Difficult to find and delete books
- 🔒 Requires Dropbox access, no local file support
- 🔍 Small thumbnail size makes it hard to browse

**Reported bugs**

- Crashes when opening certain PDF files
- Corrupted files cause repeated crashes
- Dropbox integration issues on some devices

**Requested features**

- Add support for ePub and other popular formats
- Implement iCloud/Google Drive integration
- Allow manual rearrangement of bookshelf
- Add dark mode and customizable background options
- Improve bookmark and annotation features


### きくPDF

[App page](https://appshunter.io/ios/app/pdf-pdf/id6819943736)

**Features:** Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 全機能のアンロック | $5.99 | one-time |


## Frequently asked questions

### Is SideBooks free?

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

### Is きくPDF free?

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

### Do SideBooks or きくPDF have ads?

Neither SideBooks nor きくPDF shows ads.

### Which is updated more often, SideBooks or きくPDF?

SideBooks ships an update every 9 days, and きくPDF every 4 days. Most recently, SideBooks was updated on November 8, 2026 and きくPDF on November 1, 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.*