Japan’s most selected EPUB viewer provides
accurate reproduction of vertical-layout and
ultrafast display of fixed-layout.

A reliable EPUB viewer with a proven track record,
it is used in more than 220*1 eBook services.

“PUBLUS™ Reader“ is a viewer that brings the capability to handle the complexities of Japanese vertical text and high-speed display of compliant to EPUB, the global eBook standard.
As the core technology of the eBook store solution PUBLUSTM, PUBLUS Reader has earned a strong following in the market.

The app version “PUBLUSTM Reader for Apps” (iOS, Android, Windows, Mac) and the web browser version “PUBLUSTM Reader for Browser” (supports all major browsers) form a lineup boasting the most advanced technology in the industry and have an ample track record making them capable to cope with the diversity of the most recent business needs.

Reasons for Being Selected

01 No. 1 commercial track record

More than 100 companies, including four major Japanese publishers, leading eBook stores, large eBook agencies use it to implement 220 plus eBook services making it the Number 1 commercial viewer in Japan. *1

※1 Based on our research as of September 2018.

02 Excellent usability

The EPUB viewer operates smoothly even at blazing speed.
Supporting recent trends, the viewer enables both vertical and horizontal flicking and vertical scrolling.

03 Rich expression

The fixed version for comics or magazines enables optimized expression of images. The reflow layout used in novels is capable of accurately reconstructing the complex vertical composition of Japanese text.
Since it supports clickable maps, audio and video, it can provide highly expressive eBook offerings.

Since a large number of publishers have adopted PUBLUS Reader, such publishers can easily check the EPUB viewer if it displays correctly what they offer.

04 Industry standard technology

The viewer conforms to The Electronic Book Publishers Association of Japan, EPUB 3 in addition to KADOKAWA-EPUB or OMF (Open Manga Format) and adopted the most recent EPUB specifications and industry trends at an early stage.
This technology is also used as the sample reference viewer of the IDPF/Readium Project or Japan Electronic Book Publishing Association.

ACCESS is a member company of the W3C, a non-profit organization working towards the standardization of web technology and license its technology to “Advanced Publishing Laboratory(APL),” an organization conducting research into and promoting the standardization of EPUB in Japan, and proactively participates with standardization organizations to contribute to the development and diffusion of specifications.


Use Cases


  • Introduction and promotion of new titles at the company own website.
  • Implementation of EPUB viewer to start up a company eBook service.
  • Upgrade of viewer to expand functionality and performance of an existing eBook service.

eBook stores

  • Unifying both fixed layout and reflow layout in the same viewer.
  • Electronic distribution of magazines and free papers.
  • Creating a multi-device EPUB format viewer.
[ Notes ]
If you consider high-performance eBook text services or educational services using PDF, pleas also consider using PUBLUS Lite.

2 Products

PUBLUS Reader comprises two products, an app version and a browser version.
Select the viewer that best suits the purpose.

PUBLUS Reader for Apps (native app version)

For viewing in an environment not connected to the Internet.

Key Specifications
Supported functions
Platforms iOS/Android/Windows/Mac *2
Content formats EPUB, JPEG, PDF *3
Video and Audio Supports embedding in EPUB content, links and clickable maps
DRM and social DRM The customer will have to implement this feature themselves *4
Method for obtaining content Supports Hybrid (both download and streaming) *5
Fixed layout/reflow layout Supports the fixed layout (comics/magazines) and the reflow layout (novels)
Usability Supports vertical and horizontal flicking and vertical scrolling
Notes at the end of the book Insert at the end of the book, SNS share button
Advertising page Supports insert
Character search The reflow layout enables character search
  • *2 Supports the most recent and the previous OS.
  • *3 JPEG and PDF use converter tools.
  • *4 Provides DRM functionality when implemented together with PUBLUS.
  • *5 Only streaming is provided for the fixed layout. The high-speed fixed viewer is supported when only a fixed layout is used.

PUBLUS Reader for Browser (browser version)

Can be viewed via streaming.

Major Specifications
Supported functions
Platforms Multi-platforms. For information on multi-platforms, refer to "OS and browsers supported as standard"
Content formats EPUB, JPEG, PDF *6
Video and Audio Supports links and clickable maps
DRM and social DRM Obfuscation/high obfuscation implemented *7
Method for obtaining content Supports streaming
Fixed version/reflow version The fixed layout (comics/magazines) and the reflow layout (novels) are supported
Usability Supports vertical and horizontal flicking and vertical scrolling
Notes at the end of the book Insert at the end of the book, SNS share button
Advertising page Supports insert
Character search, marker in the text Character search is available in the reflow layout *8
  • *6 JPEG and PDF can be supported using converters. The Webtoon format based on JPEG is also supported.
  • *7 High obfuscation is a paid option.
  • *8 Character search and the marker function are paid options provided with PUBLUS Text Server.

PUBLUS Text Server

In the reflow layout of “PUBLUS Reader for Browser,” you can use the cloud service “PUBLUS Text Server” (option) for character search and acquisition of location information. This service enables federated searches not only of book contents but all books handled.

OS and browsers supported as standard

Most recent and the previous version of OS and the following recent browsers

OS Supported browsers
iOS Safari
Android Chrome
Mac Safari, Chrome
Windows Edge, Chrome, IE11 (during the Microsoft support period)

The above standard browsers are supported as of July 1, 2018.


Operating Environment

The following operating environment is recommended for both PUBLUS Reader for Apps and PUBLUS Reader for Browser as of July 2018.

Supported OS Operating Environment
iOS iPhone: iPhone 6 or later
iPad: iPad Air or later
Android CPU: Snapdragon 808 or the equivalent or better
Memory: 2 GB or more
Mac CPU: 2 or more cores, 32-bit or 64-bit processor
Memory: 2 GB or more
Windows CPU: 2 or more cores, 32-bit or 64-bit processor
Memory: 2 GB or more

ACCESS, together with a number of other Japanese companies, is certified as an “AWS Service Delivery Partner” and is the company with the largest scale of eBook deliveries in Japan using Amazon AWS.
In the use of EPUB Viewer, we propose use of methods for secure delivery of content and CDN (Content Delivery Network).

EPUB is an electronic book file format standard that the “IDPF,” the organization set up to establish a standard for electronic book publishing, is specifying and promoting.
In February 2017, the “IDPF” was combined into the World Wide Web Consortium “W3C.”
As a member company, ACCESS participates in determining the specifications, thereby contributing to the technology licensing and dissemination activities.