Estimate thickness and angle from the Duo hinge
Does Hinge Caliper work on iPhone Duo?
Yes, the developer says so: close the Duo on an object and Hinge Caliper estimates its thickness from the hinge angle, with an optional readout on the outer display.
- App Store confirmedDaniel Hohler Designs, the developer, in the App Store description for version 1.0 (released October 12, 2026), which says the Duo's hinge works as a caliper, a protractor and a ruler. The App Store seller is D-Cade LLC.
Adapted for the fold
We're waiting on details of exactly what Hinge Caliper changes for the fold. Are you the developer? Tell us.
About Hinge Caliper
Hinge Caliper estimates an object’s thickness from the Duo’s opening angle, and can hold or speak a reading. The developer warns against using it where precise measurements are critical. Its description offers an optional readout on the outer display while the camera runs.
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: "Hinge Caliper turns the hinge of iPhone Duo into a measuring tool." (version 1.0, released October 12, 2026).
App version: 1.0.
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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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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