Today we are excited to announce version 6.10.6 of PDFTron's iOS SDK .

This release adds a OCG layer browser, real-time collaboration support, measurement calibration, customizable controls, and more.

OCG layer browser

A PDF OCG (Optional Content Groups) dictionary represents a collection of graphic objects in a document that can be made visible or invisible. Any graphic content of a PDF can be made optional, including page contents, XObjects, and annotations.

This release adds a new OCG layer browser control to Tools.framework that can be used to selectively enable and disable OCG layers in a document.

OCG layer list control.

Please see our guide for more information on the OCG layer browser control.

Real-time collaboration support

Real-time collaboration support has been expanded and is now included in Tools.framework. It allows realtime synchronization of annotations and notes between users, and is designed to be quickly and easily integrated with any backend server. The Collaboration sample included with the SDK .DMG download has also been updated to include a WebViewer Server backend in addition to the existing Firebase backend. For more information please see our collaboration guide .

Measurement calibration

Distance, perimeter, and area measurement annotations can now be calibrated to a reference value in a document. For example, a floor plan or map might have a distance scale that defines the distances on the page. To calibrate a distance measurement annotation, you would create the annotation aligned with the document's distance scale and then from the annotation's "Calibrate" selection menu item set the measurement annotation's value to match the distance scale. The measurement annotation can then be moved and resized and its value will be relative to the document's distance scale.

Measurement calibration.

For more information on measurement annotations please see our dedicated guide .

Customizable controls

The PTDocumentViewController class uses many of the other controls included in the Tools project, like the page thumbnail browser and annotation list . This makes it easy to add a full-featured document viewer to any project but because the individual controls are created internally by PTDocumentViewController, before this release it could be difficult to customize those controls.

All controls used by PTDocumentViewController can now be customized and overridden with the PTOverrides system. Just create a subclass of the control you want to customize, like PTAnnotationToolbar , override or extend the control's behavior in your subclass, and register the subclass with PTOverrides. Your custom control will then be used automatically by any PTDocumentViewController!

For more information please see our class overriding guide .

And more...

This release also adds properties to the PTPDFViewCtrl class for getter/setter methods for a more natural experience in Swift and Objective-C.

As always, please see the 6.10.6 changelog for a full list of changes in this release.

We hope you like these changes and any feedback is greatly appreciated. Please don't hesitate to contact us if you have any questions or suggestions. We also have many more exciting new features planned for the coming weeks and months, so stay tuned!