A nano-texture layer scatters the light that would show the iPhone Duo's crease

Shoppers who corner a reviewer ask one question first. TechRadar's reviewer wrote that the folding phone curious consumers he talks to all ask him the same thing: is there a crease ^[9]. The same hands-on answers it: "The crease is gone on the iPhone Duo. I can feel it with my finger, but cannot see it, because Apple decided to put a special nano-texture covering on the main display" ^[6].

Folding a stack that includes thin glass leaves "a tiny bit of curvature remaining when you unfold," according to the same account ^[24], so the coating is doing its work on the light. TechRadar says the crease on the Galaxy Z Fold 8 Ultra is slightly perceptible in certain lighting ^[8].

The right-side dock is the part that lands on design teams. Between folded and unfolded the diagonal grows from 5.4 inches to 7.6 ^[1], about 41 percent more ^[20], and the system's own controls on that bigger canvas sit on one side. A left-handed user has no confirmed setting to flip them ^[3]. The session was also brief: "I didn't get a ton of time with this star of the show," the reviewer wrote ^[21]. That is enough to describe a layout. A design bar for foldable apps generally would take more than one short session, and the account carries no developer detail at all.

The handoff test is the useful part for anyone shipping an app on this thing. Open something on the cover screen, unfold slowly, and the session moves across; the reviewer tried it with a game and with Netflix and called it "perfection, a precision of connection that should please users" ^[10]. The OS carries the transition. Whether an app holds its scroll position and its playback state through that resize is the app team's problem.

Other details read like first-generation friction. The reviewer could not reliably fold and unfold one-handed, managed it with two hands, and found the hinge solid and able to hold at varying degrees of open ^[11]. StandBy mode was not obvious without docking the phone or putting it to sleep ^[12]. Splitting the main screen between Photos and Messages worked by dragging an app in ^[13].

For a team planning work before the hardware lands, the split is whether the canvas changes or the hands change. Canvas work means holding state across a mid-task resize, and it comes first, because the OS-level handoff assumes it and it holds no matter which side the dock ends up on. Hands work means the right-weighted layout, and the mirror option is undocumented ^[3], so a design built around a right thumb may have to be rebuilt around a left one.