The iOS SDK (formerly iPhone SDK) is a software development kit developed by Apple Inc. and released in February 2008 to develop native applications for iOS.
History
On October 17, 2007, in an open letter posted to Apple's "Hot News" weblog, Steve Jobs announced that a
software development kit (SDK) would be made available to third-party developers in February 2008. The SDK was released on March 6, 2008, and allows developers to make applications for the iPhone and iPod Touch, as well as test them in an "iPhone simulator". However, loading an application onto the devices is only possible after paying an iPhone Developer Program fee, which is $99.00 USD.
Since the release of
Xcode 3.1, Xcode is the development environment for the iOS SDK. iPhone applications, like iOS and Mac OS X, are written in
Objective-C.
SDK release history
{|class="wikitable"
|-
!|Version
!|Build
!|Date
!|Notes
|-
||iOS 1.2b1 Beta 1
||5A147p
||March 6, 2008
||Release for iPhone OS version 1.2b1. Announced at an Apple Town Hall meeting.
|-
||iOS 2.0b2 Beta 2
||5A225c
||March 27, 2008
||Release for iPhone OS version 2.0b2, which added
Interface Builder, an application for building
graphical user interfaces for iPhone applications.
|-
||iOS 2.0b3 Beta 3
||5A240d
||April 8, 2008
||Release for iPhone OS version 2.0b3.
|-
||iOS 2.0b4 Beta 4
||5A258f
||April 23, 2008
||Release for iPhone OS version 2.0b4. This version of the SDK supports OpenGL 3D graphics, primarily used to make games, and indications that some applications will be allowed to run in the background (as the iPod, Phone, and Mail applications do), something that Apple had previously stated was not possible.
|-
||iOS 2.0b5 Beta 5
||5A274d
||May 6, 2008
||Release for iPhone OS version 2.0b5.
|-
||iOS 2.0b6 Beta 6
||5A292g
||May 28, 2008
||Release for iPhone OS version 2.0b6. The code in this update gave hints about updates to Apple's
.Mac service and also gave a first reference to the upcoming version of
Mac OS X, version
10.6 Snow Leopard.
|-
||iOS 2.0b7 Beta 7
||5A331
||June 9, 2008
||Release for iPhone OS version 2.0b7, which unlocked Apple's .Mac replacement,
MobileMe. This release was for
WWDC, Apple's developer's conference, which is noted as part of the name of the iPhone OS beta download.
|-
||iOS 2.0b8 Beta 8
||5A345
||June 26, 2008
||Release for iPhone OS version 2.0b8.
|-
||iOS 2.0 Final
||
||July 11, 2008
||Release for iPhone OS version 2.0. This coincided with the launch of the App Store.
|-
||iOS 2.1 Beta 1
||5F90
||July 24, 2008
||Release for iPhone OS version 2.1. Apple notes that applications built using the 2.1 SDK will not run on the iPhone 2.0 software, and will not yet be accepted into the App Store.
|-
||iOS 2.1 Beta 2
||
||July 30, 2008
||Release for iPhone OS version 2.1.
|-
||iOS 2.1 Beta 3
||
||August 8, 2008
||Release for iPhone OS version 2.1.
|-
||iOS 2.1 Beta 4
||
||August 16, 2008
||Release for iPhone OS version 2.1.
|-
||iOS 2.1 Final
||
||September 12, 2008
||Release for iPhone OS 2.1.
|-
||iOS 2.2 Beta 1
||5G29
||September 25, 2008
||Release for iPhone OS version 2.2.
|-
||iOS 2.2 Beta 2
||
||October 24, 2008
||Release for iPhone OS version 2.2.
|-
||iOS 2.2 Final
||9M2621
||November 20, 2008
||Release for iPhone OS version 2.2.
|-
||iOS 2.2.1
||9M2621a
||January 27, 2009
||Release for iPhone OS version 2.2.1.
|-
||iOS 3.0 Beta 1
||
||March 17, 2009
||Preview of iPhone OS version 3.0 and SDK 3.0 beta release.
|-
||iOS 3.0 Beta 2
||
||March 31, 2009
||Release for iPhone OS version 3.0.
|-
||iOS 3.0 Beta 3
||
||April 14, 2009
||Release for iPhone OS version 3.0.
|-
||iOS 3.0 Beta 4
||
||April 28, 2009
||Release for iPhone OS version 3.0.
|-
||iOS 3.0 Beta 5
||
||May 6, 2009
||Release for iPhone OS version 3.0.
|-
||iOS 3.0 Golden Master
||
||June 8, 2009
||Final Release for iPhone OS version 3.0 for developers and private testers only.
|-
||iOS 3.0 Final
||
||June 17, 2009
||Final release for iPhone OS version 3.0 for standard users was released on June 17.
Since its release, there has been some controversy regarding the refund policy in the fine print of the Developer Agreement with Apple. According to the agreement that developers must agree to, if someone purchases an app from the app store, 30% of the price goes to Apple, and 70% to the developer. If a refund is granted to the customer (at Apple's discretion), the 30% is returned to the customer from Apple, and 70% from the developer; however, Apple can then take another 30% of the cost from the developer to make up for Apple's loss.
SDK contents
As iOS uses a variant of the same
XNU kernel that is found in
Mac OS X, the
tool chain used for developing on iOS is also based on
Xcode.
The SDK is broken down into the following sets:
Cocoa Touch
*Multi-touch events and controls
*Accelerometer support
*View hierarchy
*Localization (i18n)
*Camera support
Media
*OpenAL
*audio mixing and recording
*Video playback
s
*Quartz
*Core Animation
*OpenGL ES
Core Services
*Networking
*Embedded SQLite database
*Core Location
*Threads
*CoreMotion
OS X Kernel
*TCP/IP
*Sockets
*Power management
*Security
Along with the Xcode toolchain, the SDK contains the iPhone Simulator, a program used to emulate the look and feel of the iPhone on the developer's desktop. Originally called the Aspen Simulator, it was renamed with the Beta 2 release of the SDK. Note that the iPhone Simulator is not an emulator and runs code generated for an x86 target.
The SDK requires an Intel Mac running Mac OS X Snow Leopard or later. Other operating systems, including Microsoft Windows and older versions of Mac OS X, are not supported.
Core Location
Core Location is a software framework in iOS. It is primarily used by applications on iPhone OS 2.0 for detection of the device's location. On the iPod Touch, Core Location uses
Skyhook Wireless's
Wi-Fi-based positioning system. On the original iPhone, it uses
cellular tower triangulation in addition to Wi-Fi positioning. On the iPhone 3G and 3GS, it also uses the available
GPS hardware, on the iPhone 3GS and iPhone 4 it also uses the compass. The actual selection of location method is abstracted from the user and developer.
It was announced as part of the iPhone Software Roadmap event on March 6, 2008, and was made available as part of the iOS SDK.
SVG
Mobile Safari supports
SVG starting with iPhone OS 2.1. The SVG support features scripting and most of the static parts of the SVG 1.1. specification.
SMIL animation is not yet supported for SVG graphics. It will be delivered after the
Webkit SMIL implementation is mature enough. In addition to SVG, the
HTML Canvas is supported.
Other development languages
Java
Apple has not announced any plans to enable
Java to run on the iPhone.
Sun Microsystems announced plans to release a
Java Virtual Machine (JVM) for iOS, based on the
Java Platform, Micro Edition version of Java. This would enable Java applications to run on iPhone and iPod Touch.
Soon after the announcement, developers familiar with the SDK's terms of agreement believed that by not allowing 3rd-party applications to run in the background (answer a phone call and still run the application, for example), allowing an application to download code from another source, or allowing an application to interact with a 3rd-party application (Safari with JVM, for example), could hinder development of the JVM without Apple's cooperation.
It is clear that Java running on the iPhone is outside the bounds of the iOS SDK Agreement. The guideline in question is rule 3.3.2, which reads:
However, some iPhone users have shown that it was possible to install and use a J2ME stack on an iPhone, though it involved jailbreaking.
It has also been revealed that there were talks between Sun and Apple concerning the availability of Java on the iPhone, and that Sun was working in that intent with a company called Innaworks. Since it is required that all ARM9 or later processors include Jazelle support, the iPhone includes the hardware for accelerated Java execution.
.NET/CLI
It is not permissible to install a
.NET Framework or similar runtime on an iPhone, but by using
Novell's commercial
MonoTouch framework it is possible to achieve similar results. MonoTouch uses a custom fork of the
Mono Project to compile all
CLI bytecode in .NET to native ARM machine-code ahead of time.
Since this framework is fully compatible with CLI compliant languages that do not emit runtime compiled code is is possible to develop with the wide range of languages supported by .NET, including C# and Visual Basic .NET.
Flash
iOS does not support
Adobe Flash, and Flash movies on web pages cannot be viewed in Mobile
Safari. Although Adobe has two versions of its software - Flash and Flash Lite - Apple views neither as suitable for the iPhone, claiming that full Flash would be too cumbersome for the iPhone, while Flash Lite would not provide a worthy experience for the users.
Flash for Apple is a virtual machine with a just-in-time compiler. Apple's iOS SDK prevents any software on the iPhone from downloading or running external executable code (e.g. a virtual machine). Additionally, apps built under the iPhone Developer Program License Agreement for the iPhone SDK 4 Beta may not be originally written in any other programming language than C, C++, or Objective-C. What Adobe had done in their CS5 release for the iPhone was to create a static compiler that allows developers to compile their flash programs into apps that can run on the iPhone. This would have allowed many Flash games to become apps, but still preventing web interfaces such as Hulu from working on the iPhone. But as these apps wouldn't have been originally written in C, C++ or Objective-C, they may not pass the App Store approval process when done under the terms of the iPhone SDK 4 Beta.
Unofficially, some Flash video sites can be viewed by using a jailbroken iPhone with certain third-party applications. However, it results on extremely low frame rate due to the lack of memory bandwidth and CPU speed for Flash JIT execution. Another reason is the general lack of optimization of Flash for iOS, which can be seen in several benchmarks of Flash in OS X.
Since November 2009, Adobe has posted the following notice on the Flash download page when viewed from an iPhone:
“Flash Player not available for your device
Apple restricts use of technologies required by products like Flash Player. Until Apple eliminates these restrictions, Adobe cannot provide Flash Player for the iPhone, iPod Touch and iPad.”
Licensing
The SDK itself is a free download but in order to release software, one must enroll in the
iPhone Developer Program—a step requiring payment and Apple's approval. , cost of enrollment in the iPhone Developer Program is
US$99 per year (the cost varies from country to country) for the standard program. Signed keys are provided to upload the application to Apple's App Store. Applications can be distributed in three ways: through the App Store, through enterprise deployment to a company's employees only, and on an "Ad-hoc" basis to up to 100 iPhones. Once distributed through the App Store, a developer can request up to 50 promotional codes that can be used to freely distribute a commercial application he or she has developed. The SDK can only be installed in
MacOS.
External links
Notes
References
Category:IOS (Apple)
