---
title: "読書尚友 - 青空文庫ビューア — App Overview"
url: https://marlvel.ai/intel-report/book/app--817
category: Book
developer: hishida
platforms: ios
rating: 4.0 (1 ratings)
pricing: free
report_level: overview
generated: 2026-05-04
last_verified: "2026-05-04T14:49:50.809Z"
---

<!-- SECTION: Key Insight -->
> **Key Insight:** This app serves as a highly functional, free reader that bridges the gap between Aozora Bunko's extensive library and local file management with robust vertical-text support.

<!-- SECTION: Quick Facts -->
| Metric | Value |
|--------|-------|
| Category | Book |
| Rating | 4.0 ★ (1) |
| Pricing | free |
| Platforms | iOS |
| Latest Version (iOS) | 1.28 |
| Developer | hishida |

<!-- SECTION: Summary -->
## What is 読書尚友 - 青空文庫ビューア?

読書尚友 is an iOS document viewer optimized for Japanese vertical text, specifically designed for reading Aozora Bunko literature. It supports a wide range of file formats including PDF, ePub, and OOXML, offering advanced customization for reading comfort.

<!-- SECTION: Key Features -->
## Key Features

- **Multi-format Support**: Handles diverse file types including text, HTML, PDF, OOXML, ODT, ePub, htmlz, images, and ZIP archives.
- **Aozora Bunko Integration**: Provides direct access to over 10,000 works with features for downloading, searching by author or category, and viewing access rankings.
- **Customizable Reading Experience**: Allows users to adjust font size, font type, background settings, and page orientation, including support for vertical and horizontal layouts.
- **Advanced Navigation and Annotation**: Includes marker functionality, document-wide string search, and automatic table of contents generation based on Aozora Bunko annotations.

<!-- SECTION: Target Audience -->
## Who is it for?

Japanese literature enthusiasts and users who require a versatile, vertical-text-capable document reader for local and cloud-based files.

<!-- SECTION: Links -->
## Links

- [App Store](https://apps.apple.com/us/app/%E8%AA%AD%E6%9B%B8%E5%B0%9A%E5%8F%8B-%E9%9D%92%E7%A9%BA%E6%96%87%E5%BA%AB%E3%83%93%E3%83%A5%E3%83%BC%E3%82%A2/id1579254502?uo=4)
- [Full Intelligence Report](https://marlvel.ai/intel-report/book/app--817)

---
*This is an overview report. Sentiment analysis, competitive landscape, and SWOT analysis are available in the [full intelligence report](https://marlvel.ai/intel-report/book/app--817).*
*Generated by [Marlvel.ai](https://marlvel.ai) — Independent app intelligence.*