Introduction to eSignatures and Digital Signatures on iOS

PSPDFKit facilitates paperless signing workflows with the Electronic Signatures and Digital Signatures components. These are two components that can be licensed separately and don’t depend on each other.

Electronic Signatures

Electronic signatures let users create signatures from ink drawings, bitmap images, and text. It includes a built-in UI for adding and deleting signatures in documents with or without a signature form element. Annotations are used under the hood to execute the electronic signing process. The Electronic Signatures component also contains support for programmatically marking ink or image annotations as signatures. See our guide on adding an electronic signature to learn more.

Electronic Signatures introduces support for three different modes of adding signatures: draw, image, and type. This allows you to integrate a feature-rich signing experience inside your app. Please see our guide on customizing the signature user interface to learn about available API options.

You can also implement callbacks to provide signature storage so that users can reuse their electronic signatures across documents.

Digital Signatures

Digital Signatures are signatures that are signed with a certificate. This signing approach is different from the one supported by Electronic Signatures, since digital signatures have a unique fingerprint identifying the signer and are reliable proof of the document’s origin and protection against modification by third parties. Check out our Digital Signatures guides for more information.

Electronic Signatures and Digital Signatures are inherently different, but they can under some circumstances work together — for example, by using the Electronic Signatures UI to let the user create a drawing or select an image, and using this for the appearance of a generated digital signature. To learn more, see our guide on using Electronic Signatures and Digital Signatures together.

ℹ️ Note: For more information on digital signatures, please look at the Digital Signatures in a PDF guide by Adobe. You should also take a look at the 12.8 Digital Signatures section of Adobe’s PDF 1.7 specification. For general information on how digital signatures work, please read the digital signature entry on Wikipedia.

Older Signatures Functionality

For PSPDFKit licenses obtained in April 2021 or earlier, limited signatures functionality is included with the Annotations component. This older signatures functionality will continue to be maintained and supported. However, we recommend using Electronic Signatures for new PSPDFKit integrations. Please read our migration guide to learn how to move from the older signatures functionality to Electronic Signatures.