A ruler, tape measure and camera ruler, now supporting the Duo
Does Ruler® work on iPhone Duo?
Yes. Ruler®'s App Store page says it supports iPhone Duo, so the update is out. FoldHunt's editor hasn't seen it running yet.
- App Store confirmedThe developer, in the release notes for version 3.8.6 (released September 28, 2026): "Added support for iPhone Duo." The notes say nothing more. There are no pictures of it on the Duo yet. The App Store seller is Tue Nguyen Minh (id 623207505).
Adapted for the fold
We're waiting on details of exactly what Ruler® changes for the fold. Are you the developer? Tell us.
About Ruler®
Ruler® measures objects on the screen, with a tape measure and a camera ruler too. Version 3.8.6 adds iPhone Duo support, without saying what changes. There are no pictures of it on the Duo yet.
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 3.8.6 (released September 28, 2026) mention iPhone Duo: "Added support for iPhone Duo."
App version: 3.8.6.
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 ↗
Related guides
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.
Do your apps work on iPhone Duo? What happens before they're updated
Every iPhone app opens on iPhone Duo, but only updated ones fill the inner display. What an app looks like before its developer adapts it, how to tell which are ready, and which popular apps have said so.
Is this your app?
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More for iPhone Duo
KeepCount
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Simulator verified: Tyler Hillsman, the developer, in a submission to FoldHunt on October 17, 2026, with an unframed screenshot of the app in the iPhone Duo simulator in the press kit (keepcount.app). The App Store seller is 1881 Digital, LLC. The release notes for version 1.8 (released October 12, 2026) say KeepCount now adapts to the iPhone Duo's inner and outer displays, with a tabletop layout when it's partly folded.
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Simulator verified: Panoramic Software Inc., the developer, in a submission to FoldHunt on October 18, 2026, and in the App Store release notes for version 7.0.6 (released October 12, 2026), which describe the closed and open layouts. The app's page on the developer's website has pictures of both on the iPhone Duo.
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Simulator verified: Tyler Hillsman, the developer, in the App Store release notes for version 5.4.0 (released October 13, 2026), which add iPhone Duo support with a larger library and side-by-side editing, and in a submission to FoldHunt on October 17, 2026, with an unframed screenshot of the app in the iPhone Duo simulator in the press kit (stickywidgets.app). The App Store seller is 1881 Digital, LLC; the App Store pictures show ordinary iPhones and iPads.
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