15-03-2011, 11:34 AM
SUBMITTED BY
AJAYAN JOY
[attachment=10189]
introduction
Android is a software stack for mobile devices that includes an operating
system, middleware and key applications. Android is a software platform and
operating system for mobile devices based on the Linux operating system and developed by Google and the Open Handset Alliance. It allows developers to write managed code in a Java-like language that utilizes Google-developed Java libraries, but does not support programs developed in native code.
The unveiling of the Android platform on 5 November 2007 was announced with the founding of the Open Handset Alliance, a consortium of 34 hardware, software and telecom companies devoted to advancing open standards for mobile devices. When released in 2008,most of the Android platform will be made available under the Apache free-software and open-source license
1.1. THE BIRTH OF ANDROID
1.1.1.Google Acquires Android Inc.
In July 2005, Google acquired Android Inc., a small startup company based in Palo
Alto, CA. Android's co-founders who went to work at Google included Andy Rubin
(co-founder of Danger), Rich Miner (co-founder of Wildfire Communications, Inc),
Nick Sears (once VP at T-Mobile), and Chris White (one of the first engineers at
WebTV). At the time, little was known about the functions of Android Inc. other
than they made software for mobile phones.
At Google, the team, led by Rubin, developed a Linux-based mobile device OS
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.
1.1.2.Open Handset Alliance Founded
On 5 November 2007, the Open Handset Alliance, a consortium of several
companies which include Google, HTC, Intel, Motorola, Qualcomm, T-Mobile,
Sprint Nextel and NVIDIA, was unveiled with the goal to develop open standards
for mobile devices. Along with the formation of the Open Handset Alliance, the
OHA also unveiled their first product, Android, an open source mobile device
platform based on the Linux operating system.
1.1.3.Hardware
Google has unveiled at least three prototypes for Android, at the Mobile World
Congress on February 12, 2008. One prototype at the ARM booth displayed several
basic Google applications. A 'd-pad' control zooming of items in the dock with a
relatively quick response.
A prototype at the Google IO conference on May 28, 2008 had a 528 MHz
Qualcomm processor and a Synaptics capacitive touch screen, and used the UMTS
cellular standard. It had 128 MB of RAM and 256 MB of flash, showing that
Android's memory requirements are reasonable. The demo was carried out using a
3.6 Mbit/s HSDPA connection.
1.2. FEATURES
1.2.1.Application Framework
It is used to write applications for Android. Unlike other embedded mobile
environments, Android applications are all equal, for instance, an applications
which come with the phone are no different than those that any developer
writes.The framework is supported by numerous open source libraries such as openssl, SQLite and libc. It is also supported by the Android core libraries.
From the point of security, the framework is based on UNIX file system
permissions that assure applications have only those abilities that mobile phone owner gave them at install time.
1.2.2.Dalvik Virtual Machine
It is extremely low-memory based virtual machine, which was designed especially
for Android to run on embedded systems and work well in low power situations. It
is also tuned to the CPU attributes. The Dalvik VM creates a special file format
(.DEX) that is created through build time post processing. Conversion between
Java classes and .DEX format is done by included “dx” tool.
1.2.3.Integrated Browser
Google made a right choice on choosing WebKit as open source web browser. They
added a two pass layout and frame flattening. Two pass layout loads a page without waiting for blocking elements, such as external CSS or external
JavaScript and after a while renders again with all resources downloaded to the device. Frame flattening converts founded frames into single one and loads into the browser. These features increase speed and usability browsing the internet via mobile phone.
1.2.4.Optimized Graphics
As Android has 2D graphics library and 3D graphics based on OpenGL ES
1.0, possibly we will see great applications like Google Earth and spectacular
games like Second Life, which come on Linux version. At this moment, the
shooting legendary 3D game Doom was presented using Android on the mobile
phone.
1.2.5.SQLite
Extremely small (~500kb) relational database management system, which is integrated in Android. It is based on function calls and single file, where all
definitions, tables and data are stored. This simple design is more than suitable for a
platform such as Android.
1.2.6.Handset Layouts
The platform is adaptable to both larger, VGA, 2D graphics library, 3D graphics
library based on OpenGL ES 1.0 specifications, traditional smart phone layouts. An
underlying 2D graphics engine is also included. Surface Manager manages access to
the display subsystem and seamlessly composites 2D and 3D graphic layers from
multiple applications
1.2.7.Data Storage
SQLite is used for structured data storage .SQLite is a powerful and lightweight
relational database engine available to all applications.
1.2.8.Connectivity
Android supports a wide variety of connectivity technologies including GSM,
CDMA, Bluetooth, EDGE, EVDO, 3G and Wi-Fi.
1.2.9.Messaging
SMS, MMS, and XMPP are available forms of messaging including threaded text
messaging.
1.2.10.Web Browser
The web browser available in Android is based on the open-source WebKit
application framework. It includes LibWebCore which is a modern web browser
engine which powers both the Android browser and an embeddable web view
1.2.11.Java Virtual Machine
Software written in Java can be compiled into Dalvik bytecodes and executed in the
Dalvik virtual machine, which is a specialized VM implementation designed for
mobile device use, although not technically a standard Java Virtual Machine.
1.2.12.Media Support
Android will support advanced audio/video/still media formats such as MPEG-4,
H.264, MP3, and AAC, AMR, JPEG, PNG, GIF.
1.2.13.Additional Hardware Support
Android is fully capable of utilizing video/still cameras, touchscreens, GPS,
compasses, accelerometers, and accelerated 3D graphics.
1.2.14.Development Environment
Includes a device emulator, tools for debugging, memory and performance 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.
AJAYAN JOY
[attachment=10189]
introduction
Android is a software stack for mobile devices that includes an operating
system, middleware and key applications. Android is a software platform and
operating system for mobile devices based on the Linux operating system and developed by Google and the Open Handset Alliance. It allows developers to write managed code in a Java-like language that utilizes Google-developed Java libraries, but does not support programs developed in native code.
The unveiling of the Android platform on 5 November 2007 was announced with the founding of the Open Handset Alliance, a consortium of 34 hardware, software and telecom companies devoted to advancing open standards for mobile devices. When released in 2008,most of the Android platform will be made available under the Apache free-software and open-source license
1.1. THE BIRTH OF ANDROID
1.1.1.Google Acquires Android Inc.
In July 2005, Google acquired Android Inc., a small startup company based in Palo
Alto, CA. Android's co-founders who went to work at Google included Andy Rubin
(co-founder of Danger), Rich Miner (co-founder of Wildfire Communications, Inc),
Nick Sears (once VP at T-Mobile), and Chris White (one of the first engineers at
WebTV). At the time, little was known about the functions of Android Inc. other
than they made software for mobile phones.
At Google, the team, led by Rubin, developed a Linux-based mobile device OS
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.
1.1.2.Open Handset Alliance Founded
On 5 November 2007, the Open Handset Alliance, a consortium of several
companies which include Google, HTC, Intel, Motorola, Qualcomm, T-Mobile,
Sprint Nextel and NVIDIA, was unveiled with the goal to develop open standards
for mobile devices. Along with the formation of the Open Handset Alliance, the
OHA also unveiled their first product, Android, an open source mobile device
platform based on the Linux operating system.
1.1.3.Hardware
Google has unveiled at least three prototypes for Android, at the Mobile World
Congress on February 12, 2008. One prototype at the ARM booth displayed several
basic Google applications. A 'd-pad' control zooming of items in the dock with a
relatively quick response.
A prototype at the Google IO conference on May 28, 2008 had a 528 MHz
Qualcomm processor and a Synaptics capacitive touch screen, and used the UMTS
cellular standard. It had 128 MB of RAM and 256 MB of flash, showing that
Android's memory requirements are reasonable. The demo was carried out using a
3.6 Mbit/s HSDPA connection.
1.2. FEATURES
1.2.1.Application Framework
It is used to write applications for Android. Unlike other embedded mobile
environments, Android applications are all equal, for instance, an applications
which come with the phone are no different than those that any developer
writes.The framework is supported by numerous open source libraries such as openssl, SQLite and libc. It is also supported by the Android core libraries.
From the point of security, the framework is based on UNIX file system
permissions that assure applications have only those abilities that mobile phone owner gave them at install time.
1.2.2.Dalvik Virtual Machine
It is extremely low-memory based virtual machine, which was designed especially
for Android to run on embedded systems and work well in low power situations. It
is also tuned to the CPU attributes. The Dalvik VM creates a special file format
(.DEX) that is created through build time post processing. Conversion between
Java classes and .DEX format is done by included “dx” tool.
1.2.3.Integrated Browser
Google made a right choice on choosing WebKit as open source web browser. They
added a two pass layout and frame flattening. Two pass layout loads a page without waiting for blocking elements, such as external CSS or external
JavaScript and after a while renders again with all resources downloaded to the device. Frame flattening converts founded frames into single one and loads into the browser. These features increase speed and usability browsing the internet via mobile phone.
1.2.4.Optimized Graphics
As Android has 2D graphics library and 3D graphics based on OpenGL ES
1.0, possibly we will see great applications like Google Earth and spectacular
games like Second Life, which come on Linux version. At this moment, the
shooting legendary 3D game Doom was presented using Android on the mobile
phone.
1.2.5.SQLite
Extremely small (~500kb) relational database management system, which is integrated in Android. It is based on function calls and single file, where all
definitions, tables and data are stored. This simple design is more than suitable for a
platform such as Android.
1.2.6.Handset Layouts
The platform is adaptable to both larger, VGA, 2D graphics library, 3D graphics
library based on OpenGL ES 1.0 specifications, traditional smart phone layouts. An
underlying 2D graphics engine is also included. Surface Manager manages access to
the display subsystem and seamlessly composites 2D and 3D graphic layers from
multiple applications
1.2.7.Data Storage
SQLite is used for structured data storage .SQLite is a powerful and lightweight
relational database engine available to all applications.
1.2.8.Connectivity
Android supports a wide variety of connectivity technologies including GSM,
CDMA, Bluetooth, EDGE, EVDO, 3G and Wi-Fi.
1.2.9.Messaging
SMS, MMS, and XMPP are available forms of messaging including threaded text
messaging.
1.2.10.Web Browser
The web browser available in Android is based on the open-source WebKit
application framework. It includes LibWebCore which is a modern web browser
engine which powers both the Android browser and an embeddable web view
1.2.11.Java Virtual Machine
Software written in Java can be compiled into Dalvik bytecodes and executed in the
Dalvik virtual machine, which is a specialized VM implementation designed for
mobile device use, although not technically a standard Java Virtual Machine.
1.2.12.Media Support
Android will support advanced audio/video/still media formats such as MPEG-4,
H.264, MP3, and AAC, AMR, JPEG, PNG, GIF.
1.2.13.Additional Hardware Support
Android is fully capable of utilizing video/still cameras, touchscreens, GPS,
compasses, accelerometers, and accelerated 3D graphics.
1.2.14.Development Environment
Includes a device emulator, tools for debugging, memory and performance 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.
