Agenda
What is android?
Why ?
Application Components
Practical matters

Introduction
 Android is an operating system for mobile
devices such as cellular phones, tablet
computers and net books.
 It was initially developed by Android Inc.
which was later purchased by Google.
 Google further formed the open handset
alliance.

Open Handset Alliance
 The Open Handset Alliance (OHA) is a business
alliance of 78 firms for developing
open standards for mobile devices
 Technically the term “ OPEN STANDARDS “ refers
to a specification whose description is freely
available .
 This means that developers are free to create
applications which are valid according to the
specification and which will therefore work with
software designed for it.

Some major names in OHA
 HTC
 SAMSUNG ELECTRONICS
 MOTOROLA
 GOOGLE
 NVIDIA ELECTRONICS
 INTEL CORP
 EBAY
 SONY ERRICSON

Android is open source.
 The source code of the android operating system is
freely available to anyone.
 Being an open source it has the following
advantages:
1. Support
2. Cost
3. Flexibility

ANDROID ARCHITECTURE

LINUX KERNEL
 Android relies on Linux version 2.6 for core system
services such as security, memory management,
process management, network stack, and driver
model.
 The kernel also acts as an abstraction layer between
the hardware and the rest of the software stack.

Dalvik Virtual Machine
 The Dalvik VM takes the generated Java class files and
combines them into one or more Dalvik executable
(.dex) files.
 It reuses duplicate information from multiple class
files, effectively reducing the space requirement
(uncompressed) by half from a traditional .jar file.
 For example, the.dex file of the web browser app in
Android is about 200K, whereas the equivalent
uncompressed .jar version is about 500K.

 Second, Google has fine-tuned the garbage collection
in the Dalvik VM.
 Finally, the Dalvik VM uses a different kind of
assembly-code generation, in which it uses registers as
the primary units of data storage instead of the
stack.30 % fewer instructions are accomplished as a
result.
 We should point out that the final executable code in
Android, as a result of the Dalvik VM, is based not on
Java byte code but on .dex files instead.

Android 2.2 FROYO
Released may 2010,
the Froyo was the
most awaited and
rumored edition of
the android till
date.

Future Aspects
 Google android operating system can be used in
net books :
 Net books are now the fastest growing segment of the
PC market, they are portable, functional and
comparatively inexpensive. It would make easier for
users of Android powered phones to share information
between pc.

Building Blocks
Activities
Layout file
R.Java
Androidmanifest.xml

 Important Classes:
 Activity
 Intent
 Services
 BroadCastReceivers
 ContenrProviders

Some Interesting APPS
Lets take a look at some of
innovative applications that have
been developed for the android.

Virtual qwerty with SWYPE technology
 This application produces a virtual
qwerty for the user
 It has an additional feature that you don’t have to lift
your finger from the screen in order to type a word
 The word is automatically guessed, based upon the
characters travelled across

Conclusion
 Android is a big revolution in the field of operating
system.
 Its custom virtual machine optimize memory and
hardware resources in a mobile environment. It can be
liberally extended to incorporate new cutting edge
technologies as they emerge.
 The open source platform will continue to evolve as the
developer community works together to build
innovative mobile applications.

THANKING YOU