Apple’s iPhone Duo includes a little-known display setting that adds a narrow black border on the left side of its outer screen. Reporting from hands-on discovery indicates the option appears in the iPhone Duo’s Display & Brightness menu as “Shift Left Edge,” increasing the left-side border width compared with the default display view.
The purpose described by outlets is to improve compatibility with phone cases that slightly cover the left edge of the foldable display. By shifting the visible edge, the setting is intended to help preserve correct behavior for on-screen gestures, including the iOS back swipe that relies on the left side of the display. Both outlets note Apple also provides official iPhone Duo cases, but it remains unclear whether those specific accessories require the adjustment. Differences in emphasis center on how outlets frame the setting’s target use—either as support for cases that cover the left edge, potentially including third-party options—or more generally as an accommodation feature. Pre-orders are reported to begin October 16, with availability starting October 23.
