Cocoa Touch
UIKit
For iOS, the Cocoa Touch frameworks focus on touch-based interfaces and optimization. The UIKit provides the basic tools and infrastructure you need to implement graphical, event-driven apps in iOS.

Foundation
The building blocks of any Cocoa app, including collection classes and all the base objects used throughout Cocoa.
Multi-Touch Gestures
The iOS frameworks include APIs to alert you to many standard gestures, or you can hand-code your own gesture awareness.
Network Services
Store Kit
Unlock features, sell new services, and provide added value to your app using the Store Kit framework to enable in-app purchases of new content.

Push Notifications
Send over-the-air alerts, such as news updates or social networking status changes, using Apple’s Push Notification service.
Game Kit
Easily add multi-player capabilities to your games with peer to peer network connectivity, using a Bluetooth connection - no pairing required.
iAd
Embed iAd rich media ads into your app that allow users to interact with advertising without having to leave their app.Learn more

Newsstand
Newsstand Kit provides everything you need to publish the latest issues of your magazines and newspapers directly to Newsstand. Learn more
Core Location
Using information from the present network connection, and GPS signals where available, your app can quickly determine the present location.


Map Kit
Add map features directly into your app, with full support for panning and zooming, custom annotations, showing current location, and even geocoding to highlight regions of the map and display additional information. Use projected map coordinates instead of regions, or use overlays (such as circles or rectangles) to display content over a wide portion of the map.
Networking
BSD sockets for standard network communication, and Bonjour for a simple way to discover other devices on the network.
Accelerate
Accelerate provides hundreds of mathematical functions optimized for iPhone and iPod touch, including signal-processing routines, fast Fourier transforms, basic vector and matrix operations, and industry-standard functions for factoring matrices and solving systems of linear equations. Optimized for the different hardware configurations present in iOS-based devices, Accelerate lets you write code once that you can be assured will run efficiently on all devices.
Media

Graphics
Frameworks range from Quartz 2D primitives, the easy-to-use Core Animation for awesome effects, to industry standard OpenGL ES for creating spectacular 3D games.
Audio
Everything for playing videos, music, and in-game media: Media Player framework for full-screen video, HTTP Live Streaming, access to the iPod library, and Core Audio and OpenAL for sound.

Built-in Cameras and Photo Library
Import images from the device’s photo library, or easily take a new photo to add to your app. Create augmented reality experiences with a live camera feed and overlays.

Media Library
Play music in the background of your app and access the full media library on the device.
Core Services

iOS Simulator
The Mac-based Simulator speeds the round trip process of developing with fast app startup, and accelerated stepping through the debugger.
Inter-app Messaging
Easily share data with the iOS system apps using a simple URL-based model, or register a custom URL type to enable sharing with your own app.
Messaging
Add support in your app for composing and queuing email messages in the user’s outbox, and for sending SMS messages from within your app.

In-App SMS
Compose SMS messages from within apps, similar to the Mail compose sheet added iniOS SDK 3.0.
Cut, Copy, and Paste
System-wide support for cut, copy, and paste makes it easy to share more than just plain words to and from your app, with support for rich text, HTML, and images using a shared clipboard.

Gyro + Accelerometer
The three-axis gyroscope paired with the accelerometer makes an iOS device capable of advanced motion sensing such as user acceleration, full 3D attitude, and rotation rate. Combined with Core Motion, these features allow your app to use both the accelerometer and gyro-based data for games or other apps that use motion as input or as a way to enhance the overall user experience.

Multitasking
iOS delivers multitasking services that allow your apps to perform tasks in the background while preserving battery life and performance.

Address Book
Read and write to the device’s shared contacts database so your app can tie into a central repository of friends, family, and coworkers.

Compass
Full access to the hardware compass, when available, to employ along with location and map services, also available as core services of iOS.
Electronic Accessories
Create a great experience for hardware devices using a custom app on an iOS device to control the accessory.
Quick Look
Apps can now present previews of documents, like attachments in Mail, using the new Quick Look APIs. Quick Look lets you preview the contents of files your app does not support. Intended primarily for apps that download files from the network, Quick Look lets you display the contents directly in your app.