--- title: "Nutrient iOS SDK 27.1 release notes" canonical_url: "https://www.nutrient.io/guides/ios/releases/27-1/" md_url: "https://www.nutrient.io/guides/ios/releases/27-1.md" last_updated: "2026-10-07T00:00:00.000Z" description: "Nutrient iOS SDK 27.1 brings progressive rendering to zoomed pages, the Content Editor, and night mode; lets you adjust the built-in signature flow; and adds a software bill of materials." --- 7 October 2026 Nutrient iOS SDK 27.1 extends progressive rendering to zoomed-in pages and more viewing modes. It also enables you to set the appearance and placement of signatures created with the built-in signing UI. Starting with this release, we produce a software bill of materials (SBOM) for every iOS SDK release. This release also fixes several issues with the Content Editor and embedded fonts, and with PDF Advanced Electronic Signatures (PAdES) validation. For the full list of changes, see the [changelog](https://www.nutrient.io/guides/ios/changelog.md#27.1.0). ## iPhone Duo iPhone Duo brings a new form factor to iOS, with a large unfolded display and safe area insets that aren’t always symmetrical. We’ve been working on making Nutrient feel at home on it. In this release, the document viewer keeps a stable layout on the unfolded display. The page label, document label, and scrubber bar now respect uneven left and right safe area insets. Your app benefits from these improvements without any code changes.![Screenshot of Nutrient iOS SDK 27.1 on an unfolded iPhone Duo in landscape, showing a two-page spread with the vertical toolbar on the right and the scrubber bar and page label centered within the safe area.](@/assets/guides/ios/releases/27-1-iphone-duo.png) ## Progressive rendering in more places [Nutrient iOS SDK 27](https://www.nutrient.io/guides/ios/releases/27.md) introduced progressive rendering, which shows partial results while a detailed page, such as a building plan, is still rendering. Some cases still waited for the full render: zooming in; pages with a rotation offset; and night, sepia, and grayscale modes. Custom page background colors, page tint, and editing text with the [Content Editor](https://www.nutrient.io/sdk/content-editor/) also waited. Nutrient iOS SDK 27.1 renders these progressively too. When you zoom in and move around a page, the zoomed area fills in step by step instead of staying blurry until it’s finished. As before, progressive rendering is enabled by default and needs no code changes. ## Customize the built-in signature flow You can now adjust signatures without replacing the built-in signing UI. Set [`defaultLineWidth`](https://www.nutrient.io/api/ios/documentation/pspdfkitui/signaturecreationviewcontroller/configuration-swift.struct/defaultlinewidth) and [`defaultAlpha`](https://www.nutrient.io/api/ios/documentation/pspdfkitui/signaturecreationviewcontroller/configuration-swift.struct/defaultalpha) on [`SignatureCreationViewController.Configuration`](https://www.nutrient.io/api/ios/documentation/pspdfkitui/signaturecreationviewcontroller/configuration-swift.struct) to change the stroke width and opacity. Implement [`pdfViewController(_:placeSignature:)`](https://www.nutrient.io/api/ios/documentation/pspdfkitui/pdfviewcontrollerdelegate/pdfviewcontroller(_:placesignature:completionhandler:)) to decide where a signature goes before it’s added to the document. See the [`SignatureAppearanceAndPlacementExample`](https://github.com/PSPDFKit/pspdfkit-ios-catalog/blob/master/Catalog/Examples/Annotations/SignatureAppearanceAndPlacementExample.swift) in the Catalog app for both in action. ## Software bill of materials We now produce a [CycloneDX](https://cyclonedx.org/) SBOM for every release. It lists the third-party components bundled in the SDK, along with their versions. If your organization needs an SBOM for security or compliance reviews, contact [Nutrient Support](https://www.nutrient.io/support/request/) or your account manager. --- ## Related pages - [14 12](/guides/ios/releases/14-12.md) - [26 1](/guides/ios/releases/26-1.md) - [26 10](/guides/ios/releases/26-10.md) - [26 11](/guides/ios/releases/26-11.md) - [26 12](/guides/ios/releases/26-12.md) - [26 2](/guides/ios/releases/26-2.md) - [26 3](/guides/ios/releases/26-3.md) - [26 4](/guides/ios/releases/26-4.md) - [26 5](/guides/ios/releases/26-5.md) - [26 6](/guides/ios/releases/26-6.md) - [26 7](/guides/ios/releases/26-7.md) - [26 8](/guides/ios/releases/26-8.md) - [26 9](/guides/ios/releases/26-9.md) - [26](/guides/ios/releases/26.md) - [27](/guides/ios/releases/27.md)