andriod overview is discussed in this document which will be usefull to get an idea about android and its aplications

1. ANDROID OVERVIEW
By
B.Vamsi Reddy[IT] P.V.Sai Teja[CSE]
Bhavanam.vamsireddy@gmail.com saiteja.friends@gmail.com
GUNTUR ENGINEERING COLLEGE
YANAMADALA,NH-5,GUNTUR

2. ABSTRACT:
Android is a software stack for mobile 2.announced with the founding of the
devices that includes an operating system, Open Handset Alliance, a consortium
middleware and key applications. Android of 34 hardware, software and telecom
is a software platform and operating companies devoted to advancing open
system for mobile devices based on the standards for mobile devices. When
Linux operating system and developed by released in 2008, most of the Android
Google and the Open Handset Alliance. It platform will be made available under
allows developers to write managed code the Apache free-software and open-
in a Java-like language that utilizes source license.
Google-developed Java libraries, but does THE BIRTH OF ANDROID:
not support programs developed in native
code. The unveiling of the Android 1.Google Acquires Android Inc.
platform on 5 November 2007 was
2. Open Handset Alliance Founded
announced with the founding of the Open
Handset Alliance, a consortium of 34 3. Hardware
hardware, software and telecom companies
devoted to advancing open standards for FEATURES
mobile devices. When released in 2008, 1. Application Framework
most of the Android platform will be made
It is used to write applications
available under the Apache free-software
for Android. Unlike other embedded
and open-source license.
mobile environments, Android
applications are all equal, for instance, an
applications which come with the phone
1.INTRODUCTION are no different than those that any
Android is a software stack for mobile developer writes.The framework is
devices that includes an operating system, supported by numerous open source
middleware and key applications. Android libraries such as openssl, SQLite and libc.
is a software platform and operating It is also supported by the Android core
system for mobile devices based on the libraries. From the point of security, the
Linux operating system and developed by framework is based on UNIX file system
Google and the Open Handset Alliance. It permissions that assure applications have
allows developers to write managed code only those abilities that mobile phone
in a Java-like language that utilizes owner gave them at install time.
Google-developed Java libraries, but does 2. Dalvik Virtual Machine
not support programs developed in native It is extremely low-memory based virtual
code. machine, which was designed especially
The unveiling of the Android platform on for Android to run on embedded systems
5 November 2007 was and work well in low power situations. It
is also tuned to the CPU attributes. The
Dalvik VM creates a special file format

3. (.DEX) that is created through build time graphic layers from multiple applications
post processing. Conversion between Java 7. Data Storage:
classes and .DEX format is done by SQLite is used for structured
included dx tool. data storage .SQLite is a powerful and
3. Integrated Browser: lightweight relational database engine
Google made a right choice on choosing available to all applications.
WebKit as open source web browser. They 8. Connectivity:
added a two pass layout and frame Android supports a wide variety of
flattening. Two pass layout loads a page connectivity technologies including GSM,
without waiting for blocking elements, CDMA, Bluetooth, EDGE, EVDO, 3G and
such as external CSS or external Wi-Fi.
JavaScript and after a while renders again 9. Messaging:
with all resources downloaded to the SMS, MMS, and XMPP are available
device. Frame flattening converts founded forms of messaging including threaded
frames into single one and loads into the text messaging.
browser. These features increase speed and 10. Web Browser:
usability browsing the internet via mobile The web browser available in Android is
phone. based on the open-source WebKit
4. Optimized Graphics: application framework. It includes
As Android has 2D graphics library and LibWebCore which is a modern web
3D graphics based on OpenGL ES 1.0, browser engine which powers both the
possibly we will see great applications like Android browser and an embeddable web
Google Earth and spectacular games like view.
Second Life, which come on Linux 11. Java Virtual Machine:
version. At this moment, the shooting Software written in Java can be compiled
legendary 3D game Doom was presented into Dalvik bytecodes and executed in the
using Android on the mobile phone. Dalvik virtual machine, which is a
5. SQLite: specialized VM implementation designed
Extremely small (~500kb) relational for mobile device use, although not
database management system, which is technically a standard Java Virtual
integrated in Android. It is based on Machine.
function calls and single file, where all 12. Media Support:
definitions, tables and data are stored. This Android will support advanced
simple design is more than suitable for a audio/video/still media formats such as
platform such as Android. MPEG-4, H.264, MP3, and AAC, AMR,
6. Handset Layouts: JPEG, PNG, GIF.
The platform is adaptable to both larger, 13. Additional Hardware Support
VGA, 2D graphics library, 3D graphics Android is fully capable of utilizing
library based on OpenGL ES 1.0 video/still cameras, touchscreens, GPS,
specifications, traditional smart phone compasses, accelerometers, and
layouts. An underlying 2D graphics engine accelerated 3D graphics.
is also included. Surface Manager 14. Development Environment:
manages access to the display subsystem Includes a device emulator, tools for
and seamlessly composites 2D and 3D debugging, memory and performance

4. profiling, a plugin for the Eclipse IDE.
There are a number of hardware dependent
features, for instance, a huge media and
connections support, GPS, improved
support for Camera and simply GSM
telephony. A great work was done for the
developers to start work with Android
using device emulator, tools for debugging
and plugin for Eclipse IDE.
Android provides the support for
the Qualcomm MSM7K chipset family.
For instance, the current kernel tree
2. DETAILED DESCRIPTION OF THE supports Qualcomm MSM 7200A
TOPIC chipsets, but in the second half of 2008 we
should see mobile devices with stable
OPERATION version Qualcomm MSM 7200, which
1. Android Runtime includes major features:
2. Linux Kernel -WCDMA/HSUPA and EGPRS network
support
ARCHITECTURE
-Bluetooth 1.2 and Wi-Fi support
The following diagram shows the major
-Digital audio support for mp3 and other
components of the Android operating
formats
system. Each section is described in more
-Support for Linux and other third-party
detail below
operating systems
-Java hardware acceleration and support
for Java applications
-Qcamera up to 6.0 megapixels
-gpsOne “ solution for GPS
-and lots of other.

5. Libraries
In the next level there are a set of native
libraries written in C/C++, which are
responsible for stable performance of Application Framework
various components. For example, Surface After that, there is Application
Manager is responsible for composing Framework, written in Java language. It is
different drawing surfaces on the mobile a toolkit that all applications use, ones
screen. It manages the access for different which come with mobile device like
processes to compose 2D and 3D graphic Contacts or SMS box, or applications
layers.OpenGL ES and SGL make a core written by Google and any Android
of graphic libraries and are used developer. It has several components.
accordingly for 3D and 2D hardware The Activity Manager manages the life
acceleration. Moreover, it is possible to circle of the applications and provides a
use 2D and 3D graphics in the same common navigation back stack for
application in Android. The media applications, which are running in
framework was provided by PacketVideo, different processes. The Package Manager
one of the members of OHA. It gives keeps track of the applications, which are
libraries for a playback and recording installed in the device. The Windows
support for all the major media and static Manager is Java programming language
image files. FreeType libraries are used to abstraction on the top of lower level
render all the bitmap and vector fonts. For services that are provided by the Surface
data storage, Android uses SQLite. As Manager.
mentioned before, it is extra light rational
management system, which locates a
Application Layer
single file for all operations related to
At the top of Android Architecture we
database. WebKit, the same browser used
have all the applications, which are used
by Applesâ„¢ Safari, was modified by
by the final user. By installing different
Android in order to fit better in a small
applications, the user can turn his mobile
size screens.
phone into the unique, optimized and
Android Runtime
smart mobile phone. All applications are
At the same level there is Android
written using the Java programming
Runtime, where the main component
language.
Dalvik Virtual Machine is located. It was
designed specifically for Android running DEVELOPING APPLICATIONS
in limited environment, where the limited
battery, CPU, memory and data storage are 1. Application Building Blocks
the main issues. Android gives an The major building blocks are
integrated tool dx, which converts these:
generated byte code from .jar to .dex file, 1 Activity
after this byte code becomes much more 2 Intent Receiver
efficient to run on the small processors 3 Service

6. 4 Content Provider . SECURITY ISSUES
2. AndroidManifest.xml Android mobile phone platform is
going to be more secure than
Here is an example of Appleâ„¢s iPhone or any other device
AndroidManifest.xml file: in the long run. There are several
1. <xml version="1.0" encoding="utf-8"> solutions nowadays to protect Google
2. <manifest phone from various attacks. One of
xmlns:android="http://schemas.android.co them is security vendor McAfee, a
m/apk/res/android" member of Linux Mobile (LiMo)
3. package="dk.mdev.android.hello"> Foundation. This foundation joins
4. <application particular companies to develop an
android:icon="@drawable/icon"> open mobile-device software platform.
5. <activity class=".HelloAndroid" Many of the companies listed in the
android:label="@string/app_name"> LiMo Foundation have also become
6. <intent-filter> members of the Open Handset Alliance
7. <action (OHA).
android:value="android.intent.action.MAI As a result, Linux secure coding
N" /> practice should successfully be built
8. <category into the Android development process.
android:value="android.intent.category.L However, open platform has its own
AUNCHER"/> disadvantages, such as source code
9. </intent-filter> vulnerability for black-hat hackers. In
10. </activity> parallel with great opportunities for
11. </application> mobile application developers, there is
12. </manifest> an expectation for exploitation and
3.Application Lifecycle:- harm. Stealthy Trojans hidden in
animated images, particular viruses
passed from friend to friend, used for
spying and identity theft, all these
threats will be active for a long run.
Another solution for such attacks is
SMobile Systems mobile package.
4. Application Framework SecurityShield “an integrated
application that includes anti-virus,
SOFTWARE DEVELOPMENT:
anti-spam, firewall and other mobile
The feedback on developing
protection is up and ready to run on the
applications for the Android platform
Android operating system. Currently,
has been mixed. Issues cited include
the main problem is availability for
bugs, lack of documentation,
viruses to pose as an application and
inadequate QA .The first publicly
do things like dial phone numbers,
available application was the Snake
send text messages or multi-media
game.
messages or make connections to the
Internet during normal device use. It is
possible for somebody to use the GPS

7. feature to
track a personâ„¢s location without
their knowledge. Hence SMobile
Systems is ready to notify and block
these secure alerts. But the truth is that REFERENCES:
it is not possible to secure your mobile 1. http://www.android.com - Android
device or personal computer Official Webpage
completely, as it connects to the 2. http://code.google.com/android/ -
internet. And neither the Android Official Android Google Code Webpage
phone nor other devices will prove to 3. http://www.openhandsetalliance.com/ -
Open Handset Alliance Webpage
be the exception.
4. http://www.androidwiki.com “
Android Wiki
5. http://googleblog.blogspot.com/ -
3. CONCLUSION AND FUTURE
Official Google Blog
SCOPE:
6.
Android has been criticized for not being
http://en.wikipedia.org/wiki/Android_(mo.
all open-source software despite what was
..œWikipedia Information
announced by Google. Parts of the SDK
7. http://en.wikipedia.org/wiki/SQLite
are proprietary and closed source, and
8. http://en.wikipedia.org/wiki/WebKit
some believe this is so that Google can
9.
control the platform. Software installed by
http://en.wikipedia.org/wiki/Eclipse_(soft
end-users must be written in Java, and will
ware)
not have access to lower level device
10. http://www.itworld.com
APIs. This provides end-users with less
control over their phone's functionality
Reference:
than other free and open source phone
http://seminarprojects.com/Thread-
platforms, such as OpenMoko.
android-full-report#ixzz1oi4xatzT
With all upcoming applications and mobile
services Google Android is stepping into
the next level of Mobile Internet. Android
participates in many of the successful open
source projects. That is, architect the
solution for participation and the
developers will not only come but will
play well together. This is notable contrast
with Apple and other companies, where
such architecture of participation is clearly
belated.
The first Android based official devices
may well be launched sometime in the
early half of 2009. Obviously, that's an age
away when it comes to handset design, and
Android may well find itself competing
against the forthcoming Nokia touch
screen phones and maybe even the iPhone