Core Video provides a pipeline model for digital video. Partitioning the processing into discrete steps makes it simpler for developers to access and manipulate individual frames without having to worry about translating between data types (QuickTime, OpenGL, and so on) or display synchronization issues. Applications that do not need to manipulate individual video frames should never need to use Core Video directly.

The Open Graphics Library (OpenGL) is used for visualizing 2D and 3D data. It is a multipurpose open-standard graphics library that supports applications for 2D and 3D digital content creation, mechanical and architectural design, virtual prototyping, flight simulation, video games, and more. You use OpenGL to configure a 3D graphics pipeline and submit data to it. Vertices are transformed and lit, assembled into primitives, and rasterized to create a 2D image. OpenGL is designed to translate function calls into graphics commands that can be sent to underlying graphics hardware. Because this underlying hardware is dedicated to processing graphics commands, OpenGL drawing is typically very fast.

High volume, cross platform push notification delivery.

SceneKit is an Objective-C framework for building apps and games that use 3D graphics, combining a high-performance rendering engine with a high-level, descriptive API. SceneKit supports the import, manipulation, and rendering of 3D assets. Unlike lower-level APIs such as OpenGL that require you to implement in precise detail the rendering algorithms that display a scene, SceneKit only requires descriptions of your scene’s contents and the actions or animations you want it to perform.

The Address Book framework provides access to a centralized contacts database, called the Address Book database, that stores a user’s contacts. Applications such as Mail and Messages use this database to present information about known and unknown persons.

In iOS and OS X, the Photos framework (formerly known as Assets Library framework) provides classes that support building photo editing extensions for the Photos app. In iOS, the Photos framework also provides direct access to the photo and video assets managed by the Photos app, including the iCloud Photo Library. Use this framework to retrieve assets for display and playback, edit their image or video content, or work with collections of assets such as albums, moments, and iCloud Shared Albums.

The AV Foundation framework provides an Objective-C interface for managing and playing audio-visual media in iOS and OS X applications.

The CloudKit framework provides interfaces for moving data between your app and your iCloud containers.You use CloudKit to take your app’s existing data and store it in the cloud so that the user can access it on multiple devices. You can also store data in a public area where all users can access it.

Core Foundation is a framework that provides fundamental software services useful to application services, application environments, and to applications themselves. Core Foundation also provides abstractions for common data types, facilitates internationalization with Unicode string storage, and offers a suite of utilities such as plug-in support, XML property lists, URL resource access, and preferences.

The Core Graphics framework is based on the Quartz advanced drawing engine. It provides low-level, lightweight 2D rendering with unmatched output fidelity. You use this framework to handle path-based drawing, transformations, color management, offscreen rendering, patterns, gradients and shadings, image data management, image creation, and image masking, as well as PDF document creation, display, and parsing.