Developers find clever uses for the iPhone Duo's two screens

Apple’s iPhone Duo, which starts at $2,000, marks the company’s first foldable phone, and initial reviews have noted that many mainstream iOS apps aren’t yet optimized for its hinged, dual-screen shape — some sit boxed in black bars or need controls enlarged by hand, echoing the early days of iPhone apps running on the iPad. But a smaller wave of apps built specifically for the Duo is what won over a TechCrunch reviewer who tested a review unit supplied by Apple, turning initial skepticism about the device’s value into interest once developers began pitching Duo-only designs.

Netflix was one of Apple’s launch partners, alongside the MLB app, NYT Cooking, Slack, and Fantastical, and its streaming app shows the format’s potential clearly: the outer screen (visible when the Duo is folded) scrolls through short-form “Clips,” while opening the device shifts playback to the larger inner display without interrupting the video. Deck-Man, a free music player from indie developer Vidit Bhargava that was previewed in September under the name Duo-Man, reimagines a Walkman cassette deck across the Duo’s two screens, complete with recorded click-and-whir sounds from an actual portable cassette player, and the reviewer called it unmissable for anyone who buys the device. Flighty, an Apple Design Award winner for flight tracking, spreads its route map to the edges of the open screen and added a Duo-only “En Route Mode” that keeps flight progress visible on a folded, tent-shaped Duo propped on a tray table while the user does something else. Tiny Computers, a $3.99 one-time-fee app with no ads or subscriptions, recreates ten retro machines — including the Macintosh, Commodore 64, and Windows 95 — for use in the Duo’s open “laptop” position, with hidden files and secret commands built in as a game layer.

Other apps mentioned adapt differently to the Duo’s folded, open, tent, and laptop positions, from a workout app that redesigns its interface per posture to a notebook app that mimics a paper journal’s page curl. The reviewer expects the list of Duo-built apps to keep growing as more developers get hardware in hand.

Why it matters

Apple’s software-developer base — which the reviewer credits for keeping them committed to the iPhone platform — is becoming the proof point for whether the Duo’s foldable format has staying power, ahead of whether mainstream apps catch up. Expect Apple to keep spotlighting Duo-native apps as a way to paper over the gap until bigger developers update their software.