i is the key letter for Apple’s portable line of
devices such as:ipod, ipodTouch,ipodShuffle, iphone, ipad, ipa
iOS is formerly known as iPhone OS.
Developed by Apple,Inc.
Released on June 29,2007
Programmed in c,c++,objective c
Available in 34 languages.
iOS mainly developed for iPhone but it can
support other devices as:
Unlike Microsoft’s windows phone and
Google’s Android Apple does not license iOS
for installation on non-Apple hardware
Latest version of iOS i.e. iOS7 was released on
September 18, 2013
Its where user keeps his stuff.
Organization of file system plays an important
role for system and apps to find and access
Goal: user should find easily.
The file system in iOS handle the
persistent storage of data files, apps, and
the files associated with the operating
The file system is one of the fundamental
resources used by all processes.
Based on Unix file system.
• Similar to basic architecture found in Mac OS X.
• Acts as intermediate between applications and
Every App is an island
An iOS app’s interactions with the file
system are limited mostly to the directories
inside the app’s sandbox.
An app is generally prohibited from
accessing or creating files in directories
outside of its home directory.
But it can use public system interfaces to
access things such as the user’s contacts or
iOS technology layers
In iOS there are 4 abstraction layers:
the Core OS layer,
the Core Services layer,
the Media layer and
the Cocoa Touch layer.
Core OS layer
The Core OS layer contains the low-level
They are most likely used by frameworks like:
External Accessory Framework.
Generic Security Services Framework.
Accelerate Framework: The Accelerate
framework contains interfaces for performing
digital signal processing (DSP),imageprocessing calculations etc
External Accessory framework: It provides
support for communicating with hardware
accessories attached to an iOS-based device.
Security Framework: iOS also provides an
explicit Security framework that you can use
to guarantee the security of the files your app
Core services layer
These are some of the features:
Data Protection .
Mostly c based.
we can use peer-to-peer connectivity to
initiate communication sessions with nearby
iCloud storage lets your app write user
documents and data to a central location.
Users can then access those items from all of
their iOS devices
When your app designates a specific file as
protected, the system stores that file on disk
in an encrypted format. While the device is
locked, the contents of the file
inaccessible to both your app and to any
potential intruders. However, when the device
is unlocked by the user, a decryption key is
created to allow your app to access the file.
The Media layer contains the
graphics, audio, and video technologies you
use to implement multimedia experiences in
C and objective C are used.
Coca Touch layer
The key technologies available in the Cocoa Touch
AirDrop: AirDrop lets users share
photos, documents, URLs, and other kinds of data
with nearby devices.
Text Kit: Text Kit is a full-featured, high-level
technology for handling text and fine typography
Apple Push Notification Service: Apple Push
Notification service provides a way to alert users
about new information, even when your app is not
Gesture recognizers and etc.