Android a mobile Operating system

By | May 5, 2012


The Android – a mobile operating system is developed by Google team. It is an operating system for mobiles. Google  has   made   most   of   the Android   platform   available   under   the   Apache free­ software  and open  source   license. Android  is  a  freely downloadable  open   source   software   stack   for mobile devices   that   includes  an operating system, middleware and key applications based on Linux and Java.  Google developed Android collaboratively as part of  the Open Handset Alliance, a group   of more than 30 mobile and technology   companies  working   to open up  the  mobile handset environment.


Android  is   a   software platform  and  operating  system  for mobile devices, based on  the Linux kernel,  and developed by Google and  later   the Open Handset Alliance.  It  allows developers   to  write  managed   code   in   the   Java   language, controlling the device via Google­developed Java libraries. Applications   written   in   C   and   other   languages   can   be compiled to ARM native  code and run, but this development path   isn’t   officially   supported   by   Google.   Android   is available   as   open   source. Google   threw  open   the   entire source code (including network and  telephony stacks)  that  were   not   available   previously,   under   an  Apache   license. Certain parts  that relate to a  specific hardware can’t be made open and are not considered part  of the Android  platform. With   Apache License,  vendors  are free to add proprietary extensions without submitting those back to the open source community.  While Google’s  contributions   to  this platform are expected  to  remain open­  sourced,    the branches  could explode using varieties of licenses.


1) Acquisition by Google

In July 2005, Google acquired Android,  Inc.,  a small startup company based in Palo Alto, California, USA. Android’s  co founders who went to  work at Google included Andy Rubin,  Rich Miner,  Nick Sears and Chris White. At the time, little was known about the functions of Android, Inc. other than that they  made   software   for  mobile   phones   This   began rumors that  Google was planning  to enter the mobile phone market.  At  Google,   the   team  led by Rubin  developed a mobile device  platform powered by the  Linux kernel which they  marketed to handset makers  and carriers on the  premise  of providing  a flexible, upgradeable system. It was reported that Google   had   already   lined   up   a   series   of   hardware component  and  software  partners  and  signaled to carriers that it was open to various degrees of  cooperation on their part.  More speculation  that  Google would be entering  the mobile­phone  market   came   in   December   2006.   Reports from  the   BBC  and   The  Wall   Street   Journal   noted   that Google wanted its search and applications on mobile phones and  it  was  working hard  to deliver   that.  Print  and online media   outlets   soon   reported   rumors   that Google   was developing   a  Google­branded  handset.    More   speculation followed  reporting  that   as  Google  was  defining   technical specifications,   it was   showing   prototypes   to   cell   phone  manufacturers and  network operators.

2) Update history

Android   has   seen   a  number   of  updates   since   its  original release.   These   updates   to   the   base   operating  system typically fix  bugs and add new features. And  generally, each update to the Android  operating system  is developed  under a code name based  on a dessert item.

1.5 (Cupcake) ­ April 2009

1.6(Donut)  September 2009

2.0/2.1(Eclair)  December 2009

2.2(Froyo)  May 2010

Gingerbread ­ scheduled for Q4 2010 launch.

Honeycomb­ Scheduled for 2011 launch.


Handset   layouts:  Android can adapt   to  traditional smart  phone layouts,  as well  other VGA,  2D,  and3D graphics libraries.

  • Storage: Android uses SQLite to store all its junk­­ I mean, information.
  • Connectivity: Android supports  a wide variety of technologies,   including   Bluetooth, WiFi, GSM/EDGE, and EV­DO.
  • Messaging: MMS   and   SMS   are   available   for Android,  as  well  as   threaded   text  messaging. So you can send as many texties as you like.
  • Web Browser: Android comes pre­loaded with the Web Kit  application.  Remember, if you don’t  like it, you can always switch it out for something else later  on  thanks   to  the  open   source  nature  of   the Google Android backend.
  • Java Virtual Machine: Software you write in Java can be compiled in Dalvik Byte codes (say that five times   fast.   I   keep   ending   up  with   “Danish   light bulb”.) These can then be put into a Dalvik Virtual Machine.  Basically  more   robust   applications   are supported   than   on   some   other  Mobile  Operating Systems.
  • Media Support: Android supports a wide range of audio,   video,  media,   and   still   formats.  MPEG­4, OGG,   and   AAC   are   just   a   few   of   these. Unfortunately the Media Player as its known right now is pretty basic, although more robust offerings on are the horizon from 3rd Party developers.
  • Additional  Hardware Support: Got a touch screen you   want   to   put   to   its   full   use?   No   problem. Android   is   capable  of  utilizing  outside  hardware like  GPS,   accelerometers,   and   all   that   other   fun stuff.


The Android operating system consists of 12 million lines of code including 3 million  lines of XML, 2.8 million  lines of C, 2.1 million lines  of Java, and 1.75  million lines of C++.


The following diagram shows the major components of the Android operating system, they are:

1. Applications

2. Application framework

3. Libraries

4. Linux kernel


Android will ship with a set of core applications including an  email   client,  SMS program, calendar, maps, browser,contacts,  and others. All applications  are  written using  the java programming language.

Application Framework

Developers  have  full  access   to  the  same  framework APIs used by the core applications. The application architecture is designed   to   simplify   the   reuse   of   components;   any application can   publish   its   capabilities   and   any   other application may then  make use of those capabilities  (subject to   security  constraints   enforced   by   the   framework). This same mechanism allows components to be replaced by the user.


Android  includes a set  of C/C++  libraries used by various components of   the Android system. These capabilities  are exposed   to   developers   through   the   Android   application framework.

Android Runtime

Android includes a set of core libraries that provides most of the functionality available  in  the core  libraries of  the Java programming  language.  Every Android application runs in its own process,  with its own instance  of the Dalvik virtual machine.  Dalvik has been written so that  a device can run multiple VMs efficiently. The Dalvik VM executes files in the Dalvik Executable (.dex) format which is optimized for minimal  memory  footprint.  The VM  is   registerbased,  and runs classes compiled by a Java language  compiler that have been transformed into the .dex format by the included “dx” tool.


A central  design point  of the Android security architecture is that no application, by default, has permission to perform any   operations   that   would   adversely   impact other applications,  the operating system, or the user. This includes reading or  writing the user’s private  data such as contacts or  e­mails,   reading   or   writing   another   application’s   files, performing network access,  keeping the device awake,  etc.

An application’s process is a secure sandbox. It can’t disrupt other   applications,   except   by   explicitly   declaring   the  permissions it  needs  for additional  capabilities not provided by the basic sandbox.  These  permissions   it requests can be handled   by   the   operating   in   various  ways,   typically   by automatically allowing or disallowing based on certificates or by prompting  the user.  The permissions required by an application  are declared statically in that application, so they can be known up­front at   install   time and will  not  change after that.


The   early   feedback   on   developing   applications   for   the  Android platform was mixed.Issues cited include bugs, lack of   documentation,   inadequate  QA  infrastructure,   and   no public  issue­tracking  system.   (Google announced an issue tracker on 18 January 2008.) In December 2007,  MergeLab mobile   startup  founder   Adam   MacBeth   stated, “Functionality   is not   there,   is  poorly  documented  or  just doesn’t work. It’s clearly  not ready for prime time. ” Despite this,   Android­targeted  aplications   began   to   appear   the  week after   the platform was announced.  The first  publicly  available  application was the  Snake game.  The Android Dev Phone   is   a   SIM­unlocked   and   hardware­unlocked  device that is designed  for advanced developers.   While developers  can use  regular  consumer devices  purchased at retail to test and use their applications, some developers may  choose not  to use  a retail  device, preferring an unlocked or no­contract device.


A typical desktop operating system provides a common file system that  any application can use to store and read files that   can   be   read   by   other   applications.  Android   uses   a different system on  Android, all  application data  are private to   that   application.   However,   Android   also   provides   a standard way for an application to expose its private data to other   applications.  This   section describes   the  many  ways that  an application can  store and  retrieve data, expose  its data   to other  applications, and also how you can request  data from other applications  that expose  their data.

Android provides the following mechanisms for storing and retrieving data:

  • Preferences: A  lightweight  mechanism  to  store   and   retrieve  key value pairs  of primitive data types.  This is  typically  used to  store application preferences.
  • Files: You can store your files on  the device or on a removable storage   medium.   By   default,   other   applications   cannot access these files.
  • Databases: The   Android   APIs   contain   support   for   SQLite.  Your application can create and  use a private SQLite  database. Each  database is private to the  package that creates it.
  • Content Providers: A   content   provider   is   a   optional   component   of an application that exposes  read/write access to an  application’s  private data, subject   to  whatever   restrictions   it  wants   to impose.  Content  providers   implement   a   standard   request syntax  for  data,  and  a  standard access  mechanism  for   the returned   data.   Android   supplies   a   number   of   content providers for standard  data types,  such as personal contacts.
  • Network:Don’t forget that you can also use the network to store and retrieve    data.


Android  is a multi­process system,  where each application (and   parts  of   the   system)   runs   in  its   own   process.  Most security between  applications and  the system is enforced at the process level  through standard Linux facilities,  such as user   and   group   IDs   that   are   assigned   to   applications. Additional finer­grained   security   features   are   provided through a “permission”  mechanism that enforces restrictions on   the   specific   operations   that   a   particular   process   can perform,   and   per­URI   permissions   for   granting   ad­hoc access to specific pieces of data.


A  central   feature   of  Android   is   that   one   application   can make use of elements of other applications (provided those applications   permit   it).   For   example,   if   your   application needs   to   display   a   scrolling   list   of   images   and   another application has  developed  a  suitable   scroller  and made   it available to others,  you can call upon that scroller to do the work,    rather   than   develop   your   own.   Your  application doesn’t  incorporate the code  of the other application or link to   it.  Rather, it   simply   starts   up   that   piece   of   the   other application when the need arises.

  • Activities: They provide a visual user interface for one focused Endeavour the user can undertake.
  • Services: A  service   doesnt   have   a   visual   user interface,   but   rather   runs   in   background   for   an indefinite period of time.
  • Broadcast   receivers: They   receive   and   broadcast the announcements made.
  • Content   providers: They  make   application   data available to the user.


The Android OS can be used to power cellphones, netbooks and tablet PCs, including the Dell Streak, Samsung Galaxy Taband other devices.

The first  commercially available phone to run the Android operating   system was   the  HTC  Dream,   released   on   22 October 2008.


Android is appealing to developers

  • Android apps  can be  developed on any platform (Windows  XP and Vista,  Linux,  and Mac OS X) where   iPhone   apps   can   only   be    developed   on   a fairly new Mac.
  • iPhone apps require developers to learn Objective­C (which  is used almost  nowhere outside Apple). But   Android   is   Java   which   all   mobile   app developers are familiar with.
  • Anyone  can develop and  launch an Android app whereas Apple has strict control of their App Store.
  • Getting your iPhone app available in the App Store requires   you   to   jump   through   the   hoops   of   an approval  process which can  take 2­3 months (and could  be   rejected   for   competing  with   a  native application!) But Android apps can be available in the Android Market instantly.

Android is feature rich

Android   can   support   the   same   hardware   as   the iPhone: touchscreen,  accelerometer, GPS, WiFi SMS & still camera;  plus features that  the iPhone doesnt support: MMS, video camera & Bluetooth.

  • Android has   some   fresh  ideas   like Google  Maps street view and customisable home page.
  • Unlike the iPhone, apps on an Android handset can run   in   parallel   (eg   an   app   running   in   the background can send an alert).
  • The   Android   platform   is   open   source   and extensible by  the developer  community where  as the iPhone is controlled by Apple. Android is  appealing to manufacturers
  • Android   is   a   free   OS   so   an   Android­enabled smartphone  should   be   cheaper   than  a   normal smartphone.   All   the   major   manufacturers   are looking at using it.
  • In  the US,  AT&T has exclusive rights  to sell   the iPhone 3G  (for   the next  5 years),  but  Android  is license and operator independent.


  • Samsung, Sony ericsson, Huawei Technologies and Motorola   confirmed   that   it   was   working   on hardware products   that  would  run Android.  They have even rolled out some amazing smartphones in the market, which are Android based.
  • Lenovo   is   also   working   on   an   Android­based mobile  phone  that   supports  the  Chinese  3G TD SCDMA standard.
  • HTC has  released a “portfolio”  of  Android based phones.
  • GiiNii  Movit  Mini   is  a  Internet  device  based on Google’s Android operating system.


Android   sits   alongside   a   new wave   of  mobile   operating systems   designed   for   increasingly   powerful   mobile hardware.   Windows   Mobile   and   Apples iPhone   now provide  a  richer,   simplified development  environment  for mobile applications.  However, unlike Android,  theyre built on proprietary operating systems that often prioritize native applications over those created by third parties and restrict communication among applications and native phone data. Android offers new possibilities for mobile applications by offering an open development environment built on an open source  Linux  kernel.  Hardware   access   is   available   to   all applications   through   a   series   of   API   libraries,   and application  interaction, while  carefully  controlled,   is   fully supported.

In  Android,   all   applications   have   equal   standing.  Third­party and native Android applications are written using the same APIs and are executed on  the same run  time.  Users can  remove and replace any native application with a third­party   developer   alternative;   even   the   dialer   and  home screens can be replaced.

  • Google Android Sales to Overtake iPhone in 2012.
  • The  OHA  is   committed   to  make   their   vision a reality:  to deploy  the Android platform  for  every mobile   operator,   handset   manufacturers   and developers to build innovative devices .
  • Intel doesnt want to lose ownership of the netbook market, so  they  need   to   prepare   for  anything, including Android.
  • Fujitsu   launched   an   initiative   to  offer   consulting and engineering expertise to help run Android on embedded hardware, which aside from cellphones, mobile   internet devices,   and   portable   media players,   could   include   GPS   devices,   thin­client computers and set­top boxes.
  • More Android devices  are coming and some will push the envelope even further.


The final conclusion is  that   the Androids platform which has developed by Google is going to play major role in Mobile Operating System  and its  applications  as it is an open source and it  is also   easy   to   develop  mobile  applications  using Android. These apps turn out to be very useful in our day to day life. Android is the future of mobile operating systems.

Please Share: Tweet about this on TwitterShare on FacebookShare on Google+Share on RedditPin on PinterestShare on LinkedInDigg thisShare on StumbleUponShare on TumblrBuffer this pageShare on VKEmail this to someone

3 thoughts on “Android a mobile Operating system

  1. Tushar Shete

    Its a great & very fantastic and truly helpful website for me ..Not only me but also other all students who are belongs to technical side…
    I really like the way of your thinking about our general need in educational purpose…Thank you so much Sir..
    I think You have to publish your Website through out the world


Leave a Reply

Your email address will not be published. Required fields are marked *