Readdle apps now support the iPhone Duo, as per the latest update from Readdle. The five apps use the unfolded display for side-by-side layouts, with PDF Expert able to open two PDFs at once.
Spark shows the inbox next to the open email, and PDF Expert gets the whole toolbar on the inner display. Documents and Calendars use the extra room for files and wider calendar views, while Scanner Pro has more space to review and edit scans before you export them.
Readdle apps on the iPhone Duo use two panes for email and PDFs
Spark puts the inbox and the message you are reading next to each other once you unfold the phone. Closed, open or posed halfway, the same actions and content stay available, and the inner display adds room for reading, writing, search and the calendar. The layouts build on the resizable iPhone windows that Spark added for iOS 27.
PDF Expert shows full pages with the whole toolbar, and you can open two PDFs side by side or keep it next to another app in Split View. Fold the phone and the app returns to its compact layout, with your document, page and tool where you left them. The iPhone Duo update also improves the handwriting recognition that PDF Expert added with iOS 27.
Documents, Calendars and Scanner Pro show more on the inner display
Documents has more room for browsing files, watching video and reading PDFs and books. It also opens in Split View next to other apps, so you can drag an email attachment from Spark into Documents to convert, compress, edit or share it.
Calendars opens up wider Week, Month and Year views when you unfold the phone, and the agenda and timeline sit side by side. A sidebar sits beside the calendar for moving between views, and folding the phone brings back the compact layout.
Scanner Pro, the top pick in our iPhone document scanner roundup, gets more room to review, edit and sign a scan before you export it as a PDF, Word file, PowerPoint or JPG. Scanning modes for books and QR codes are still there, and old photos can be digitized on the larger screen.
All five apps are free to download with in-app purchases. Spark, PDF Expert and Documents received their iPhone Duo updates on October 22, a day before the phone went on sale. Calendars and Scanner Pro followed on October 23, the launch day.
