android-01 Introduction to Mobile Operating System

What is Mobile OS?

• A mobile operating system is an operating system used for smartphones, tablets, smartwatches, smart glasses
• Controls how device works
• Without OS, phone cannot function

What Mobile OS Does

• Starts device properly
• Runs applications
• Connects to internet
• Works smoothly

Examples of Mobile OS

• Android
• iOS

Why Mobile OS is Needed?

• Use apps like WhatsApp, YouTube
• Make calls and messages
• Use internet & Wi-Fi
• Control battery & memory

Features of Mobile OS

• Touch Screen Interface
• Multitasking
• Connectivity
• App Management
• Resource Management

Touch Screen Interface

• Touch screen users can use touch gestures
• Tap icons
• Swipe pages
• Easy to use

Multitasking

• Many apps run together
• Easy switching
• Example: Music + WhatsApp

Connectivity

• Mobile network
• Wi-Fi
• Bluetooth

App Management

• Download apps
• Install apps
• Update apps
• Play Store / App Store

Resource Management

• RAM management
• Battery saving
• Processor control

Constraints of Smart Mobile OS

Limited Battery Power

• Mobile phones run on battery
• Battery drains fast
• Heavy apps and games consume more power

Limited RAM (Memory)

• Mobile devices have less RAM than computers
• Too many apps make phone slow
• Background apps are closed automatically

Limited Storage Space

• Mobile storage is limited
• Apps, photos, videos fill memory quickly
• User needs to delete data often

Small Screen Size

• Mobile screens are small
• Limited space to display information
• Not suitable for long work like desktop

Limited Processing Power

• Mobile processors are less powerful
• Heavy tasks reduce performance
• Apps must be optimized

Types of Mobile OS

• Mobile Operating Systems are used to run mobile devices such as smartphones
• Different companies have developed different Mobile Operating Systems

Android

• Developed by Google
• Most widely used Mobile Operating System
• Open-source operating system
• Used in smartphones and tablets

iOS

• Developed by Apple Inc.
• Used in iPhone and iPad
• Provides smooth and secure user interface
• Closed operating system

BlackBerry OS

• Developed by BlackBerry
• Known for high security
• Mostly used by business users
• Now discontinued

Microsoft (Windows Phone)

• Developed by Microsoft
• Used in Nokia Lumia phones
• Simple and user-friendly interface
• Discontinued by Microsoft

Symbian OS

• Developed by Nokia
• Used in early Nokia smartphones
• One of the first mobile operating systems
• Now discontinued

Generalized Architecture of Mobile Operating System

• A Mobile Operating System manages mobile hardware and provides a platform for applications.

Main Layers:

• Kernel Layer
• Hardware Abstraction Layer (HAL)
• Middleware
• Application Framework
• User Interface Layer

Kernel Layer

• Core part of Mobile OS
• Manages memory
• CPU scheduling
• Power management
• Device drivers
• Based on Linux kernel

Hardware Abstraction Layer (HAL)

• Interface between hardware and OS
• Hides hardware complexity
• Makes OS portable across devices

Middleware Layer

• Provides common services
• Multimedia support
• Database services
• Security services

Application Framework & UI Layer

Application Framework:

• APIs for app development
• Manages activities and resources

User Interface Layer

• Handles display and user interaction

Comparison of Mobile Operating Systems

Feature	Android	iOS	BlackBerry	Windows Mobile	Symbian
Developer	Google	Apple	BlackBerry	Microsoft	Nokia
Source Type	Open	Closed	Closed	Closed	Open
App Store	Play Store	App Store	BB World	Windows Store	Ovi Store
Security	Moderate	High	Very High	Moderate	Low
Customization	High	Low	Low	Low	Moderate
Market Share	High	High	Very Low	Negligible	Obsolete

Android Operating System – Introduction

• Linux-based mobile operating system
• Developed by Google and Open Handset Alliance (OHA)
• Mostly programmed using Java
• Open-source and customizable

Open Handset Alliance (OHA)

• Consortium of 84 companies
• Led by Google
• Founded on 5 November 2007
• Develops open standards for Android

Features of Android

• Open-source platform
• Highly customizable
• Large number of applications
• User-friendly interface

Android Supported Services

• SMS and MMS
• Internet browser
• SQLite database
• Wi-Fi, Bluetooth, GSM, CDMA
• Audio and video media

Categories of Android Applications

• Entertainment
• Communication
• Productivity
• Social

More Categories of Android Applications

• Music and Audio
• Media and Video
• Travel and Local
• Tools and Personalization

History of Android

• Founded by Andy Rubin in 2003
• Acquired by Google in 2005
• Initially developed for cameras
• Shifted from cameras to smartphones
• Android name came from Andy Rubin’s nickname
• First Android phone launched in 2008 (HTC)

Android Versions

• Android has evolved from Android 1.0 (2008) to latest versions
• Early Android versions (1.0 & 1.1) had no dessert names
• From Cupcake to Pie, Android followed alphabetical dessert naming
• From Android 10 onwards, public dessert names were removed
• Internal codenames still exist for each version
• Every new Android version focuses on:
  • Better performance
  • Improved security
  • Enhanced user interface
  • Support for new devices and hardware

Android Versions – Evolution Summary

• Android 1.0 – 2.3 (Cupcake to Gingerbread)
  • Basic smartphone features, UI and performance improvements
• Android 3.0 (Honeycomb)
  • Tablet-specific operating system
• Android 4.0 (Ice Cream Sandwich)
  • Unified phone and tablet platform
• Android 4.1 – 4.4 (Jelly Bean to KitKat)
  • Smooth UI, better notifications, low-RAM support
• Android 5.0 – 6.0 (Lollipop & Marshmallow)
  • Material Design, runtime permissions, battery optimization
• Android 7.0 – 9.0 (Nougat to Pie)
  • Multitasking, split screen, gesture navigation
• Android 10 – 12 (Android 10, 11, 12 / 12L)
  • Privacy controls, UI redesign, tablet & foldable support
• Android 13 – 16 (Tiramisu to Baklava)
  • Advanced security, performance improvements, large-screen optimization

Android Architecture (Software Stack)

• Linux Kernel
• Native Libraries
• Android Runtime
• Application Framework
• Applications

Linux Kernel (Android)

• Base of Android architecture
• Memory management
• Power management
• Device drivers
• Process management

Native Libraries

• WebKit – Browser support
• SQLite – Database
• OpenGL – Graphics
• Media – Audio and video
• FreeType – Font support

Android Runtime

• Core libraries
• Dalvik Virtual Machine (DVM)
• Optimized for mobile devices
• Uses less memory than JVM

Application Framework

• Activity Manager
• Window Manager
• Resource Manager
• Content Providers

Applications Layer

• Built-in applications
• User-installed applications
• Uses Android framework

Building Blocks of Android Application

• Activity
• View
• Intent
• Service
• Content Provider
• Fragment
• AndroidManifest.xml

Android Activity Lifecycle

• onCreate() – Activity created
• onStart() – Activity visible
• onResume() – User interaction
• onPause() – Activity partially hidden
• onStop() – Activity not visible
• onRestart() – Activity restarted
• onDestroy() – Activity destroyed