Markdown reader: outline beside the page, Read Aloud and Summarize in every pose
Does Marko: Markdown Viewer work on iPhone Duo?
Yes, since version 2.1 on October 17, 2026, says its developer: folded it fills the cover, and open the outline sits beside the page with Summarize and Ask next to the document.
- App Store confirmedYash Banka, the developer, in a submission to FoldHunt on October 18, 2026, saying Marko was checked in the Xcode 27.1 iPhone Duo simulator in every pose and orientation, and not yet on a real Duo. The release notes for version 2.1 (released October 17, 2026) say Marko now fills both displays of the iPhone Duo, in every pose. The pictures on the site and in the App Store show other devices.
Adapted for the fold
- Closed · Outer display
The whole cover
Folded, Marko fills the outer display, with its controls in the system bar down the edge.
- Open · Inner display
Outline beside the page
Open, the outline sits beside the page, and Summarize and Ask open next to the document instead of covering it. Read Aloud keeps going when you fold or unfold, and your place in the document holds.
- Book · Partly folded
Split at the fold
Half-folded, the outline and the page divide cleanly at the fold.
About Marko: Markdown Viewer
Marko is a free, native Markdown viewer for Mac, iPad and iPhone. It shows .md files with real typography, tables, highlighted code, Mermaid diagrams and math, reads a document aloud with each sentence highlighted, and can summarize it or answer questions about it on the device with Apple Intelligence. It only views, never edits your files, and works offline.
Version 2.1, out on October 17, 2026, fills both displays of iPhone Duo in every pose. Folded, Marko uses the whole outer display. Unfolded, the outline sits beside the page, and Summarize and Ask open next to the document instead of covering it. Read Aloud keeps going when you fold or unfold, and your place holds.
Evidence reviews
What we checked, when, and what the evidence establishes. Each record preserves the support label at that check.
· App Store page reviewed
App Store confirmed · iphone-duo
The App Store release notes for version 2.1.1 (released October 18, 2026) mention iPhone Duo: "Fixes the Marko icon sitting on top of the title on the first screen of iPhone Duo."
App version: 2.1.1.
Store text only: we haven't seen the app running, and the store page doesn't show how each pose is used.
View reviewed evidence ↗· Developer statement reviewed
Developer claimed · iphone-duo
Read the developer's submission, which says Marko was checked in the Xcode 27.1 iPhone Duo simulator in every pose and orientation, and the App Store release notes for version 2.1, which describe the same layouts.
App version: Not recorded in this evidence.
The developer sent no pictures or recording of the Duo layouts. The pictures on the site, in the App Store and in the linked X post show Mac, iPad and iPhone. The developer says Marko hasn't been tried on a real Duo yet. No build was tested.
View reviewed evidence ↗
Related guides
Split View on iPhone Duo: two apps side by side
iPhone Duo is the first iPhone that can show two apps at once. How Split View works, what its limits are, and which apps are built to share the screen.
iPhone Duo poses: closed, open, book, standing and Split View
A plain-language guide to the ways you will hold iPhone Duo, what the phone itself does in each, and the apps and ideas that make the most of them. For anyone buying one, and for anyone building for it.
The best iPhone Duo apps so far (October 2026)
The apps worth installing now that iPhone Duo is on sale, from the apps Apple named as launch partners to indie apps whose developers have shown a real iPhone Duo layout, picked for what they do when you open the phone.
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Sources: Marko on the App Store (apps.apple.com) · Marko's site (yashbanka.com) · Yash Banka's post on Marko 2.0 (x.com)
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