> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/ios/basic-operations.md). # Basic operations - [Basic document operations on iOS](https://docs.apryse.com/ios/basic-operations/basics.md): Learn how to open, save, and lock PDF documents in a multithreaded environment. Get started with these essential document management tips! The Apryse iOS SDK streamlines secure document processing and - [Page color mode](https://docs.apryse.com/ios/basic-operations/basics/night-mode-ios.md): Enhance your PDF viewing experience with PDFViewCtrl's special color modes: night mode, inverted color mode, and custom color mode. Learn how to set and customize these modes for optimal readability. - [Viewer](https://docs.apryse.com/ios/basic-operations/basics/viewer.md) - [Display PDF using PDFViewCTRL on iOS](https://docs.apryse.com/ios/basic-operations/basics/viewer/pdfviewctrl.md): Learn how to display a PDF using PTPDFViewCtrl and PTDocumentController. Follow step-by-step instructions for integrating PTPDFViewCtrl into your iOS app for seamless PDF viewing. The Apryse iOS SDK s - [Customize a document view controller on iOS](https://docs.apryse.com/ios/basic-operations/basics/viewer/viewer-configuration-legacy.md): Learn how to customize the legacy PTDocumentViewController class for optimal viewing experience. Explore new developments with PTDocumentController for enhanced functionality. Customize viewer classes - [Open a document with Apryse iOS SDK](https://docs.apryse.com/ios/basic-operations/open.md): Learn how to open a document using a document view controller, tabbed document view controller, or an embedded view. Explore the features of a document viewer and how to respond to opening events. Enh - [Open using document view controller with Apryse iOS SDK](https://docs.apryse.com/ios/basic-operations/open/doc-view.md): Learn how to open a document using a document view controller. The Apryse iOS SDK streamlines secure document processing and seamlessly integrates with major frameworks like Xamarin, React Native and - [View documents using PTPDFViewCtrl with Apryse iOS SDK](https://docs.apryse.com/ios/basic-operations/open/view.md): Learn how to open a document using PTPDFViewCtrl. The Apryse iOS SDK streamlines secure document processing and seamlessly integrates with major frameworks like Xamarin, React Native and Flutter. - [Show documents in a tabbed ViewController with Apryse iOS SDK](https://docs.apryse.com/ios/basic-operations/open/doc-tabbed.md): Learn how to open a document using a tabbed document view controller. The Apryse iOS SDK streamlines secure document processing and seamlessly integrates with major frameworks like Xamarin, React Nati - [Saving documents on iOS](https://docs.apryse.com/ios/basic-operations/saving.md): Learn how to save PDF documents using PDFNet saving APIs from PTPDFDoc class. Explore different saving modes like removing unused objects, incremental saving, and linearized format for optimized stora - [Lock a PDF document on iOS](https://docs.apryse.com/ios/basic-operations/lock.md): Learn how to effectively lock a PDF document instance shared across threads to prevent crashes and undefined behavior. Explore Apryse SDK's locking principles for concurrent access in multithreaded en - [Code samples for basic document operations on iOS](https://docs.apryse.com/ios/basic-operations/samples.md): Learn how to read and write a PDF file from/to memory buffer, merge, copy, delete, rearrange PDF pages, and more with this informative guide. Ideal for dynamic PDF applications. The Apryse iOS SDK str - [APIs for Basic Document Operation on iOS](https://docs.apryse.com/ios/basic-operations/apis.md): Discover the power of PTDocumentController, PTTabbedDocumentViewController, and PTPDFViewCtrl for interactive rendering and managing PDF documents efficiently. The Apryse iOS SDK streamlines secure do --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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