A hinge-angle gauge with rulers on both displays
Does Foldmeter: Hinge Angle & Ruler work on iPhone Duo?
Yes, the developer says so: on the Duo, Foldmeter shows a live hinge angle, with rulers on both displays.
- App Store confirmedappRabauken GbR, the developer, in the App Store description for version 1.0.0 (released October 15, 2026), which says the app shows the Duo's angle to the degree, live as you fold, with ruler and diameter tools on the inner and outer displays. The App Store seller is Moya, Manuel und Jonas, Sebastian GbR.
Adapted for the fold
We're waiting on details of exactly what Foldmeter: Hinge Angle & Ruler changes for the fold. Are you the developer? Tell us.
About Foldmeter: Hinge Angle & Ruler
Foldmeter turns an iPhone into a measuring tool and the Duo into a folding rule. It shows the hinge angle in large digits with a side-view diagram of the phone, and can keep three readings. Ruler and diameter tools work on the inner and outer displays.
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 description mentions iPhone Duo: "Foldmeter turns your iPhone into a measuring tool – and your iPhone Duo into a folding rule: unfold it and the app shows its angle to the degree, live as you fold." (version 1.0.0, released October 15, 2026).
App version: 1.0.0.
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 ↗
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Is this your app?
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Sources: Foldmeter: Hinge Angle & Ruler on the App Store (apps.apple.com)
More for iPhone Duo
KeepCount
Tyler Hillsman / 1881 Digital, LLC
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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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Sticky notes as widgets, with a larger library and side-by-side editing on the Duo
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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