Appworthy

Viewer DUO

Page-curl book & comic reader

satoshi amasaki
Download on theApp Store
Store ratingNo rating
Price$2.99Listed price
Age4+Store age rating
Size2 MBiPhone download
CategoryLifestyle
Developersatoshi amasaki

What we found

Full report

Too little checked to say Store information only. We haven’t analysed this app or read its reviews yet.

Money

  • $2.99 to download.

Not yet tested.

The store currently lists version 1.1, updated 2026-10-27.

Preview

Screenshot 1Screenshot 2Screenshot 3Screenshot 4Screenshot 5Screenshot 6

Store screenshots supplied by the developer.

About this app

The feel of turning real paper, on your screen.

Viewer DUO simulates every page as a physical sheet. Pull an edge and the paper lifts, the back shows through faintly, and a shadow falls on the page beneath. Let go and it settles at a natural speed.

On iPad and landscape iPhone the book opens as a two-page spread, just like print. On iPhone Duo the hinge becomes the spine.

• Formats — PDF / EPUB / TXT / ZIP・CBZ / RAR・CBR

• Turning — drag to follow your finger, tap an edge to turn, pinch a corner for a diagonal curl

• Spread / single page — automatic.…

From the developer’s store description.

For developers and the curious

The full report

The evidence, sources, measurements and versions behind every label above.

Findings and evidence

Not yet tested
Not yet tested. No analysis has been published for this app. A missing label is not a clean bill of health.

What reviewers report

No review coverage

No review analysis published for this app.

Measurements

2 measured · 6 not assessed

“Not assessed” means we could not measure it. It is never a zero and never a pass.

From store data and reviews

Developer replies to reviews
Not assessed
Fewer than 50 reviews scanned — too few to state a rate
Price in the store description
The store description doesn’t list prices (most don’t)
Cancelling, in the store description
The store description doesn’t say how to cancel (most don’t)
Themes reported by reviewers
Not assessed
This app's reviews have not been assessed yet
Five-star share of ratings
Not assessed
No rating histogram has been captured for this app

In the app package we scanned

No package has been scanned for this app, so nothing is published about what it ships. That is an absence of evidence, not a finding.

Sensitive permissions
Not assessed
No package has been scanned for this app
Analytics or tracking SDKs in the scanned package
Not assessed
No package has been scanned for this app
Advertising SDKs in the scanned package
Not assessed
No package has been scanned for this app
How we know

Supporting measurements: not a complete list of possible harms or positives. Measurement vocabulary 1.4 · how these are measured

Versions and dates analysed

Not yet tested

Not yet tested. No analysis has been run for this app, so there is no version or date to report.

Store update history

Each store’s release notes, as the developer wrote them. They are the developer’s words, not ours.

App Store

Version 1.1 · 2026-10-27
- New "Slide two at a time" mode: numbered images sit side by side and one swipe changes both - Import a folder of images, or several images at once, as one book - Fixed-layout EPUB comics now display correctly, with their covers - Pinch a page to zoom - Fixed freezes and failures when importing large files or files stored in iCloud - Fills the whole screen on iPhone Duo, and the fold of an open Duo becomes the spine of the book - Illustrations now appear in vertical text, each on its own page

Assessment record

Status
Not yet tested
App identifier
viewer-duo
Sources used
None recorded
Reviews read
None recorded
Package examined
No package scan
Human inspection
Not completed
How we know
Measurement vocabulary
1.4

Store facts

App Store

What the stores publish. Store ratings are the stores’ numbers, not Appworthy’s, and are never averaged across stores.

App Store

Store rating
Not supplied
Version
1.1
Updated
27 Oct 2026
Price
$2.99
Age rating
4+
Size
2 MB
Open in App Store
Developer
satoshi amasaki
Category
Lifestyle
Listing price
$2.99

No itemized purchase list is available for this listing.

Method and limits

What this report can and cannot show

What a missing label means

Not yet tested. No analysis has been published for this app, so there is no method to describe for it yet. A missing label is not a clean bill of health: it means nothing has been read, not that nothing is wrong.

Limits of this report

  • A package scan is static. It identifies code and text in one Android build. It does not measure a live ad session, test a deletion request, or count the steps needed to cancel.
  • Reviews keep their sample. A review-only charge shows distinct reviewers, the share and the sample size, and is published only once it clears that label’s published threshold. Calibration labels are machine-drafted and not yet confirmed by a person.
  • Not assessed is a state. It is never a zero and never a pass.
  • A missing label is not a clean bill of health. It means the evidence did not support one, not that the app is problem-free.
Not yet human-reviewed. A human review gives an app hands-on, recorded measurements. None has been run for this app. Hands-on inspections are not yet open.
Review thresholds Read the methodology For developers

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