Duo Fold Counter
Track fold and unfold events, posture time and daily patterns, distinguishing live, inferred and manual counts.
Julian Christopher Siebert · Utilities · $0.99
iPhone screenshots
How it uses iPhone Duo
Reads the hinge sensor while open. Optional background counting uses location activity and a magnetometer; inferred records and lifetime estimates are not physical hinge diagnostics.
App Store descriptionWritten by the developer.
How often do you really fold your phone? Duo Fold Counter counts every fold and unfold of your foldable iPhone, turns it into clear statistics and shows you how much of your hinge's estimated life you've already used. COUNTS LIVE, CATCHES UP LATER While the app is open, it reads the system hinge sensor and counts every fold and unfold in real time. Folded it while the app was closed? When you come back, Duo Fold Counter notices the change and records it as an "inferred" fold, so your history stays complete. You can also log folds manually at any time. OPTIONAL: COUNT IN THE BACKGROUND Want every fold counted, even with the app closed? Turn on "Count in background" in Settings. iOS only lets apps keep running in the background with location, so while this is on the app keeps location active – you'll always see the location indicator – and detects folds with the magnetometer: the halves of your phone contain magnets, and closing it brings one close to the compass sensor. Folds detected this way get a "sensor" badge in your history. It's off by default and uses some extra battery. STATISTICS THAT TELL A STORY • Folds per day and your total over time • Time spent folded, half open and unfolded • Opening angles: tent, laptop or flat • How long your phone usually stays unfolded • Time of day, weekdays and a weekday × hour heatmap • Where you fold: a map of your fold spots and your top 3 places (optional) • Full history of every recorded fold QUESTIONS, ANSWERED The Questions tab turns your data into plain-language insights: • When do you fold the most? • Is today busier than usual? • Which weekday is your folding day? • How long does it stay unfolded? • Do you fold more on weekends? • How long would the hinge last at this pace? • Where do you fold the most? ESTIMATED HINGE LIFETIME Set the rated number of folds (75,000 by default, adjustable) and see what percentage you've used and roughly how long your hinge will last at your current pace. WIDGETS Keep your fold count and estimated lifetime on your Home Screen and Lock Screen. PRIVATE BY DESIGN No account, no tracking, no ads. All your data stays on your device. Location is only used if you turn on background counting or "Record fold locations" – fold locations are stored on your device, and only place names are looked up via Apple Maps. MORE • English and German • Light and dark mode REQUIREMENTS Automatic counting requires a foldable iPhone with a hinge sensor. On other iPhones you can log folds manually and explore every statistic with sample data (Settings → Load sample data). Get to know your fold habits — download Duo Fold Counter today.
Duo Fold Counter on iPhone Duo: FAQ
Is Duo Fold Counter optimized for iPhone Duo?
Yes. Duo Fold Counter is Built for Duo: it uses the fold, Split View or the outer display. Verified on November 2, 2026 (Developer statement).
What does Duo Fold Counter look like on iPhone Duo?
Reads the hinge sensor while open. Optional background counting uses location activity and a magnetometer; inferred records and lifetime estimates are not physical hinge diagnostics.
How much does Duo Fold Counter cost?
Duo Fold Counter costs $0.99 on the App Store.
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