iOS

iOS

What is iOS

iOS is an application from the  foundation of iPhone, iPad, and iPod touch. Is an operating system of the mobile and windows that lead to support multifunctional on the processing of iPhone iPad and iPod.

This apps is developed by Apple Inc and distributed for Apple hardware and its powerful operating system for iDevices. 

These apps have collectively been downloaded more than 60 billion times.

 Steve Jobs in 2005 began planning the iPhone that become the best phone in the market he had a choice to either "shrink the Mac, which would be an epic feat of engineering, or enlarge the iPod". Jobs favored the former approach but pitted the Macintosh and iPod teams, led by Scott Forstall and Tony Fadell the idea was based on the develop of the great efficiency on processing multitask activity world wide.

iOS was being developed on 2007 for the application of iPhone and being extended to support Apple device such as iPod touch on September 2007 then iPad on January 2010, iPad Mini on November 2012 and the second generation of Apple Tv on September 2010

iOS play a great role on the smartphone mobile operating system and being best among the operating system on smartphone nowadays. Apple App store contained more tha 1.2 million application such that 500,000  was optimized for iPad.

The user interface have been developed friendly user and perform direct manipulation of data consist of slides, switches and buttons by using multi-touch gestures you can swipe, tap,pinch and reverse pinch.

The processor inside play a great role as an internal accelerometers that used by some application to respond the shaking of device such as rotating in three dimensions from portrait to landscape mode, crop the picture in the good design also there is undo command to reveal the previous action

  

            

iOS Versions

iOS have been developed into different versions  due to the need and performance of the iDevices.
The first generation was on June 29, 2007  became iOS  concurrently with the first iPhone.
The final 1.x series release was 1.1.5, released that stand for one year and come shortly after version 2.0.  
The second generation was on July 11, 2008 saw the public release of iPhone OS 2.0, with upgrades through version 2.2.1 made available.
The third generation June 17, 2009 was the release date for iPhone OS 3.0. Then it was updated through version 3.1.3 (release date February 2, 2010).  iOS version 3.1.3 this become the first generation iPod Touch and have iPhone OS 3.1.3 as their newest available
The iPad was introduced with iPhone OS 3.2, later updated to 3.2.2. 3.2.x versions of iPhone OS were made specifically for the iPad.
The fourth generation was iOS 4.0 that released on June 21, 2010, iOS 4.0 was released to the public and was made available only to the iPod Touch and iPhone.
This become with many features compared to the previous one that iOS 4.0 was announced to have over 1500 new APIs for developers, with the highly anticipated multitasking feature.
 The second generation of iPod Touch and become as iPhone 3G have iOS 4.2.1 as the final version available. This generation has many features such as multitasking and home screen background. The resolution of screen was modified into desired form.
The version iOS 4.2 is the first version to bring major feature parity to the iPhone and iPad. The release of the CDMA iPhone for Verizon Wireless saw a branching of iOS. The 4.2 version sequence continued for the CDMA phone while 4.3 was released for all other products.
The fifth generation was launched on June 6, 2011 Apple  iOS 5, Apple TV 4.4 beta and the iOS SDK 5 beta along with iCloud beta among other products.
This update introduced iMessage chat between devices running iOS 5, a new modification system Newsstand subscriptions, Twitter integrated into iOS, Reminders app, Enhancements to AirPlay, full integration with iCloud and over 200 new features.
 iOS 5.0 supports all iPad models, iPhone 3GS iPhone 4 GSM & CDMA, iPhone 4S, and the iPod Touch (3rd & 4th generation).
iOS 5 had only three minor additions, 5.0.1, 5.1, and 5.1.1, which were all provided as OTA and iTunes software updates..
These version was developed and upgrade in a time due the competition and skills found during manufactured such as  iOS 4.2, replaced with 4.2.1 due to a Wi-Fi bug in 4.2 beta 3 make Apple to release 2 golden masters (4.2 GM and 4.2.1 GM).
 The current release iOS 8.1.3, was released on January 27, 2015. In iOS, there are four abstraction layers the Core OS layer, the Core Services layer, the Media layer, and the Cocoa Touch layer.
The current version of the operating system iOS 8.0 was developed for carrying 1.3 - 1.5GB of the device's flash memory for the system partition, using roughly 800 MB of that partition (varying by model) for iOS itself.
This iOS  runs on the iPhone 4S and later, iPad 2 and later, all models of the iPad Mini, and the 5th-generation iPod Touch.
Apple provides major updates to the iOS via iTunes and the current version is for iPhone 4S, iPhone 5, iPhone 5C, iPhone 5S, iPhone 6, iPhone 6 Plus, iPad 2. The third and fourth generation iPad, the iPad Air. The first and second iPad Mini and the fifth generation iPod Touch




Multitasking
The idea of multitasking was to implementation in iOS to limits the work that applications in the background can perform to a limited function set, and for requiring application developers to add explicit support for it. In such the activities could be managed easily
Before iOS 4, multitasking was limited to a selection of the applications Apple included on the device. Users could, however "jailbreak" their device in order to unofficially multitask.
Multitasking is supported through seven background

1. Background location – application is notified of location changes
2. Background audio – application continues to run in the background as long as it is playing audio or video content
3. Voice over IP – application is suspended when a phone call is not in progress^[
4. Push notifications
5. Local notifications – application schedules local notifications to be delivered at a predetermined time
6. Task completion – application asks the system for extra time to complete a given task
7. Fast app switching – application does not execute any code and may be removed from memory at any time

Example in iOS 5 three new background APIs were introduced:

1. Newsstand – application can download content in the background to be ready for the user
2. External Accessory – application communicates with an external accessory and shares data at regular intervals
3. Bluetooth Accessory – application communicates with a Bluetooth accessory and shares data at regular intervals

Task completion

Task completion allows apps to continue a certain task after the app has been suspended.

 As of iOS 4.0, apps can request up to ten minutes to complete a task in the background

Game Center

Game Center is an online multiplayer "social gaming network" released by Apple. It allows users to "invite friends to play a game, start a multiplayer game through matchmaking, track their achievements, and compare their high scores on a leaderboard." iOS 5 and above adds support for profile photos.


Switching applications
This apps helps in scrollable dock-like interface appear from the button by double click the button that activate  the application switcher  such as in iOS 4.0 to iOS 6.x moving the contents of the screen up.
By Choosing an icon switches to an application. To the far left are icons which function as music controls, a rotation lock, and on iOS 4.2 and above, a volume controller.
 iOS 7 double clicking the home button also activates the application switcher. However, unlike previous versions it displays screenshots of open applications on top of the icon and horizontal scrolling allows for browsing through previous apps

Ending tasks

By holding the icons in the application switcher makes them "jiggle" in the home screen and allows the user to force quit the applications by tapping the red minus circle.
As in iOS 7  the process has become faster and easier. In iOS 7, instead of holding the icons to close them, they are closed by simply swiping them upwards off the screen. Up to three apps can be cleared at a time compared to one in versions up to iOS 6.1.6.

Siri

Siri is a personal assistant and knowledge navigator which works as an application on supported devices.

The service, directed by the user's spoken commands, can do a variety of different tasks, such as call or text someone, open an app, search the web, lookup sports information, find directions or locations, and answer general knowledge questions

Siri was updated in iOS 7 with a new interface, faster answers, Wikipedia, Twitter, and Bing support and the voice was changed to sound more human.

Siri is currently only available on the iPhone 4S and later iPhones, the fifth-generation iPod Touch, all of the models of the iPad Mini, and the third-generation and later iPad.

Unlocking

SIM Lock

The designer of iPhone was not to unlock an iPhone for use with other wireless carriers but the modification of iOS comes to solve this such as AT&T Mobility allows iPhone owners who have satisfied the requirements of their contract to unlock their iPhone.
 The Instructions to unlock the device are available from Apple but it is ultimately the sole discretion of the carrier to authorize the device to be unlocked.
This allows the use of a carrier sourced iPhone on other networks. However, because T-Mobile primarily uses a different band than AT&T for its 3G data signals, the iPhone will only work at 3G speeds on the T-Mobile 1900 MHz network.
There are programs to break these restrictions, but are not supported by Apple and most often not a permanent unlock, known as soft-unlock.

Development

The opportunity of being written the program in iDevices have been managed and allow to support the programing language in such an application can be written and complied by using Xcode 5 or later and optimized for iOS7 or later

Specifically for iOS and the 64-bit ARM architecture or previous 32-bit one. The Safari web browser supports web applications as with other web browsers..