C++

C++ is a compiled language. For a program to run, its source text has to be processed by a compiler,
producing object files, which are combined by a linker yielding an executable program. A
C++ program typically consists of many source code files (usually simply called source files).

compiler
Computers understand only one language and that language consists of sets of instructions made of ones and zeros. This computer language is appropriately called machine language.

A single instruction to a computer could look like this:

00000

10011110

A particular computer's machine language program that allows a user to input two numbers, adds the two numbers together, and displays the total could include these machine code instructions:

00000	10011110
00001	11110100
00010	10011110
00011	11010100
00100	10111111
00101	00000000

As you can imagine, programming a computer directly in machine language using only ones and zeros is very tedious and error prone. To make programming easier, high level languages have been developed. High level programs also make it easier for programmers to inspect and understand each other's programs easier.

link
 refers to the creation of a single executable file from multiple object files. In this step, it is common that the linker will complain about undefined functions (commonly, main itself). During compilation, if the compiler could not find the definition for a particular function, it would just assume that the function was defined in another file. If this isn't the case, there's no way the compiler would know -- it doesn't look at the contents of more than one file at a time. The linker, on the other hand, may look at multiple files and try to find references for the functions that weren't mentioned.
 An executable program is created for a specific hardware/system combination; it is not portable,
say, from a Mac to a Windows PC. When we talk about portability of C++ programs, we usually
mean portability of source code; that is, the source code can be successfully compiled and run on a
variety of systems.

The ISO C++ standard defines two kinds of entities:
• Core language features, such as built-in types (e.g., char and int) and loops (e.g., for-statements
and while-statements)
• Standard-library components, such as containers (e.g., vector and map) and I/O operations
(e.g., << and getline())
The standard-library components are perfectly ordinary C++ code provided by every C++ implementation.
That is, the C++ standard library can be implemented in C++ itself (and is with very
minor uses of machine code for things such as thread context switching). This implies that C++ is
sufficiently expressive and efficient for the most demanding systems programming tasks.
C++ is a statically typed language. That is, the type of every entity (e.g., object, value, name,
and expression) must be known to the compiler at its point of use. The type of an object determines
the set of operations applicable to it.

THE BASICS OF WEB HACKING: OUR APPROACH

Our approach is made up of four phases that cover all the necessary tasks during
an attack.
1. Reconnaissance
2. Scanning
3. Exploitation
4. Fix
It’s appropriate to introduce and discuss how these vulnerabilities and attacks
can be mitigated, thus there is a fix phase to our approach. As a penetration tester
or ethical hacker, you will get several questions after the fact related to how
the discovered vulnerabilities can be fixed. Consider the inclusion of the fix
phase to be a resource to help answer those questions.
Our Targets
Our approach targets three separate, yet related attack vectors: the web server, the
web application, and the web user. For the purpose of this book, we will define
each of these attack vectors as follows:
1. Web server: the application running on an operating system that is hosting
the web application. We are NOT talking about traditional computer hardware
here, but rather the services running on open ports that allow a web
application to be reached by users’ internet browsers. The web server may be
vulnerable to network hacking attempts targeting these services in order to
gain unauthorized access to the web server’s file structure and system files.
2. Web application: the actual source code running on the web server that provides
the functionality that web users interact with is the most popular
target for web hackers. The web application may be susceptible to a vast collection
of attacks that attempt to perform unauthorized actions within the
web application.
3. Web user: the internal users that manage the web application (administrators
and programmers) and the external users (human clients or customers) of the
web applications are worthy targets of attacks. This is where a cross-site scripting
(XSS) or cross-site request forgery (CSRF) vulnerabilities in the web application
rear their ugly heads. Technical social engineering attacks that target web users
and rely on no existing web application vulnerabilities are also applicable here.
The vulnerabilities, exploits, and payloads are unique for each of these targets,
so unique tools and techniques are needed to efficiently attack each of them.
Our Tools
For every tool used in this book, there are probably five other tools that can do
the same job. (The same goes for methods, too.) We’ll emphasize the tools that
are the most applicable to beginner web hackers. We recommend these tools not
because they’re easy for beginners to use, but because they’re fundamental tools
that virtually every professional penetration tester uses on a regular basis. It’s
paramount that you learn to use them from the very first day. Some of the tools
that we’ll be using include:
■ Burp Suite, which includes a host of top-notch web hacking tools, is a musthave
for any web hacker and it’s widely accepted as the #1 web hacking tool
collection.
■ Zed Attack Proxy (ZAP) is similar to Burp Suite, but also includes a free vulnerability
scanner that’s applicable to web applications.
■ Network hacking tools such as Nmap for port scanning, Nessus and Nikto for
vulnerability scanning, and Metasploit for exploitation of the web server.
■ And other tools that fill a specific role such as sqlmap for SQL injection,
John the Ripper (JtR) for offline password cracking, and the Social Engineering
Toolkit (SET) for technical social engineering attacks against web users!

Noteworthy HTTP Headers

Each HTTP cycle also includes headers in both the client request and the server
response that transmit details about the request or response. There are several of
these headers, but we are only concerned with a few that are most applicable to
our approach covered in this book.
The headers that we are concerned about that are set by the web server and sent
to the client’s browser as part of the response cycle are:
■ Set-Cookie: This header most commonly provides the session identifier
(cookie) to the client to ensure the user’s session stays current. If a hacker can
steal a user’s session (by leveraging attacks covered in later chapters), they
can assume the identity of the exploited user within the application.
■ Content-Length: This header’s value is the length of the response body in
bytes. This header is helpful to hackers because you can look for variation
in the number of bytes of the response to help decipher the application’s
response to input. This is especially applicable when conducting brute force
(repetitive guessing) attacks.
■ Location: This header is used when an application redirects a user to a new page.
This is helpful to a hacker because it can be used to help identify pages that are
only allowed after successfully authenticating to the application, for example.

The headers that you should know more about that are sent by the client’s
browser as part of the web request are:
■ Cookie: This header sends the cookie (or several cookies) back to the server
to maintain the user’s session. This cookie header value should always match
the value of the set-cookie header that was issued by the server. This header is
helpful to hackers because it may provide a valid session with the application
that can be used in attacks against other application users. Other cookies are
not as juicy, such as a cookie that sets your desired language as English.
■ Referrer: This header lists the webpage that the user was previously on when
the next web request was made. Think of this header as storing the “the
last page visited.” This is helpful to hackers because this value can be easily
changed. Thus, if the application is relying on this header for any sense of
security, it can easily be bypassed with a forged value.

Noteworthy HTTP Status Codes
As web server responses are received by your browser, they will include a status
code to signal what type of response it is. There are over 50 numerical HTTP
response codes grouped into five families that provide similar type of status
codes. Knowing what each type of response family represents allows you to gain
an understanding of how your input was processed by the application.
■ 100s: These responses are purely informational from the web server and usually
mean that additional responses from the web server are forthcoming.
These are rarely seen in modern web server responses and are usually followed
close after with another type of response introduced below.
■ 200s: These responses signal the client’s request was successfully accepted
and processed by the web server and the response has been sent back to your
browser. The most common HTTP status code is 200 OK.
■ 300s: These responses are used to signal redirection where additional
responses will be sent to the client. The most common implementation of
this is to redirect a user’s browser to a secure homepage after successfully
authenticating to the web application. This would actually be a 302 Redirect
to send another response that would be delivered with a 200 OK.
■ 400s: These responses are used to signal an error in the request from the
client.
This means the user has sent a request that can’t be processed by the
web application, thus one of these common status codes is returned: 401
Unauthorized, 403 Forbidden, and 404 Not Found.
■ 500s: These responses are used to signal an error on the server side. The most
common status codes used in this family are the 500 Internal Server Error
and 503 Service Unavailable.
Full details on all of the HTTP status codes can be reviewed in greater detail at
http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html.

Usual Arithmetic Conversions

 Most C operators perform type conversions to bring the operands of an expression to a common type or to extend short values to the integer size used in machine operations. The conversions performed by C operators depend on the specific operator and the type of the operand or operands. However, many operators perform similar conversions on operands of integral and floating types. These conversions are known as "arithmetic conversions." Conversion of an operand value to a compatible type causes no change to its value.

These conversions are performed on the operands of a binary operator to bring them to a common
type, which is then used as the type of the result:
[1] If either operand is of type long double, the other is converted to long double.
• Otherwise, if either operand is double, the other is converted to double.
• Otherwise, if either operand is float, the other is converted to float.
• Otherwise, integral promotions (§10.5.1) are performed on both operands.
[2] Otherwise, if either operand is unsigned long long, the other is converted to unsigned long
long.

• Otherwise, if one operand is a long long int and the other is an unsigned long int, then
if a long long int can represent all the values of an unsigned long int, the unsigned long
int is converted to a long long int; otherwise, both operands are converted to unsigned
long long int. Otherwise, if either operand is unsigned long long, the other is converted
to unsigned long long.
• Otherwise, if one operand is a long int and the other is an unsigned int, then if a long
int can represent all the values of an unsigned int, the unsigned int is converted to a
long int; otherwise, both operands are converted to unsigned long int.
• Otherwise, if either operand is long, the other is converted to long.
• Otherwise, if either operand is unsigned, the other is converted to unsigned.
• Otherwise, both operands are int.
These rules make the result of converting an unsigned integer to a signed one of possibly larger size
implementation-defined. That is yet another reason to avoid mixing unsigned and signed integers.

Synchronous Ethernet and IEEE 1588 in Telecommunications

would wireless mobile (based on technologies such as global system for mobile
communications (GSM), code division multiple access (CDMA) and LTE)
communications work without synchronization? Clearly it would not and Qualityof-
Service issues would arise if it were not considered.
Quality-of-Service and synchronization have always had close links. This has
been true in the TDM world where accurate synchronization is required to limit the
occurrence of slips.
Synchronization is still needed today and in future for mobile applications and
networks:
– to stabilize the radio frequencies used by the mobile base station;
– to allow efficient spectrum usage;
– to avoid radio interference between neighboring cells;
– to allow seamless hand over between cells.
Poor synchronization within a telecommunications network may have important
impacts on the end user:
– The communication can degrade (voice communication can become
inaudible).
– The throughput of data connections in the networks can reduce.
– The network’s connections (in the case of the internet) might even be totally
lost.
– In the case of mobile communications, hand over between cells could fail and
quality of experience degrade.
Ensuring a proper design for a synchronization network

Programming Style

Languages features exist to provide support for programming styles. Please don’t look at an individual
language feature as a solution, but as one building brick from a varied set which can be combined
to express solutions.
The general ideals for design and programming can be expressed simply:
• Express ideas directly in code.
• Express independent ideas independently in code.
• Represent relationships among ideas directly in code.
• Combine ideas expressed in code freely – where and only where combinations make sense.
• Express simple ideas simply.
These are ideals shared by many people, but languages designed to support them can differ dramatically.

The C++ language features most directly support four programming styles:
• Procedural programming
• Data abstraction
• Object-oriented programming
• Generic programming
However, the emphasis is on the support of effective combinations of those. The best (most maintainable,
most readable, smallest, fastest, etc.) solution to most nontrivial problems tends to be one
that combines aspects of these styles.
My ideal is language facilities that can be used elegantly in combination to support a continuum
of programming styles and a wide variety of programming techniques.
• Procedural programming: This is programming focused on processing and the design of
suitable data structures. It is what C was designed to support (and Algol, and Fortran, as
well as many other languages). C++’s support comes in the form of the built-in types, operators,
statements, functions, structs, unions, etc. With minor exceptions, C is a subset of
C++. Compared to C, C++ provides further support for procedural programming in the
form of many additional language constructs and a stricter, more flexible, and more supportiv
e type system.
• Data abstraction: This is programming focused on the design of interfaces, hiding implementation
details in general and representations in particular. C++ supports concrete and
abstract classes. The facilities for defining classes with private implementation details, constructors
and destructors, and associated operations directly support this. The notion of an
abstract class provides direct support for complete data hiding.
• Object-oriented programming: This is programming focused on the design, implementation,
and use of class hierarchies. In addition to allowing the definition lattices of classes, C++
provides a variety of features for navigating class lattices and for simplifying the definition
of a class out of existing ones. Class hierarchies provide run-time polymorphism (§20.3.2,
§21.2) and encapsulation (§20.4, §20.5).
• Generic programming: This is programming focused on the design, implementation, and use
of general algorithms. Here, ‘‘general’’ means that an algorithm can be designed to accept a
wide variety of types as long as they meet the algorithm’s requirements on its arguments.
The template is C++’s main support for generic programming. Templates provide (compiletime)
parametric polymorphism.
Just about anything that increases the flexibility or efficiency of classes improves the support of all
of those styles. Thus, C++ could be (and has been) called class oriented.
Each of these styles of design and programming has contributed to the synthesis that is C++.
Focusing exclusively on one of these styles is a mistake: except for toy examples, doing so leads to
wasted development effort and suboptimal (inflexible, verbose, poorly performing, unmaintainable,
etc.) code.

JAVASCRIPT HOW ITS WORK

JavaScript is fairly unique in the programming world. With your typical
programming language you have to write it, compile it, link it and deploy
it. JavaScript is much more fluid and flexible. With JavaScript all you
need to do is write JavaScript right into your page, and then load it into a
browser. From there, the browser will happily begin executing your code.

His first did in programming relationships between C # and java

have seen among the programming and integration that collaborative work but day kept going evident that it has collaborated with c # java.
what does c # and java what
C#
  is a multi-paradigm programming language encompassing strong typing, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines. It was developed by Microsoft within its .NET initiative and later approved as a standard by Ecma (ECMA-334) and ISO (ISO/IEC 23270:2006). C# is one of the programming languages designed for the Common Language Infrastructure.
     FAMILY OF C
JAVA
Java is a general-purpose computer programming language that is concurrent, class-based, object-oriented, and specifically designed to have as few implementation dependencies as possible. It is intended to let application developers "write once, run anywhere" (WORA),meaning that compiled Java code can run on all platforms that support Java without the need for recompilation.

This article compares the C# programming language with the Java programming language. While the focus of this article is mainly the programming languages and their features, such a comparison will necessarily also consider some platform features and some library features. For a more detailed comparison of the platforms, please see Comparison of the Java and .NET platforms.

Java and C# are similar programming languages that are statically, strongly, and manifestly typed, both are class-based object-oriented, both are designed with semi-interpretation or runtime compilation in mind, both use garbage-collection, and both are "curly brace languages" like C and C++.

Java Related to C#

 

1. After the creation of Java, Microsoft developed the C# language and C# is closely related to Java.
2. Many of C#’s features directly parallel Java. Both Java and C# share the same general C++-style syntax, support distributed programming, and utilize the same object model.
3. Though there are some differences between Java and C#, but the overall feel of these languages is very similar.
4. If you already know C#, then learning Java will be easy and vice versa
5. Java and C# are optimized for two different types of computing environments.
6. C# and Java Both Languages are drew from C++.
7. Both Languages are capable of creating cross platform portable program code.

PROGRAMMING(PROCESSING)

Open-source language and environment for learning the fundamentals of electronic art and computer programming paradigm that separates the concerns of data structures and the concurrent processes that act upon them.open source programming language and environment for people who want to create images, animations, and interactions

 Processing is an open source programming language and integrated development environment (IDE) built for the electronic arts, new media art, and visual design communities with the purpose of teaching the fundamentals of computer programming in a visual context, and to serve as the foundation for electronic sketchbooks. The project was initiated in 2001 by Casey Reas and Benjamin Fry, both formerly of the Aesthetics and Computation Group at the MIT Media Lab. One of the stated aims of Processing is to act as a tool to get non-programmers started with programming, through the instant gratification of visual feedback. The language builds on the Java language, but uses a simplified syntax and graphics programming model.

programming(modeling )

A modeling language is any artificial language that can be used to express information or knowledge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in the structure.

Modeling and Programming

Modeling and programming are often considered two different things. Programming languages are (perceived to be) different from modeling languages. DSLs are different from GPLs. But are they? Should there be a difference between the two worlds? How closely should the two approaches be integrated? In this talk I will argue that programming and modeling are really essentially the same thing; they are only different in terms of the abstraction level

We can study the differences and the similarities between these two forms of engineering. After all, if we find only similarities at some point, that may be good news. This seems a very respectful and scientific approach:

 Finally we will also perhaps agree that software engineering is some kind of composite engineering encompassing program engineering, model engineering, language engineering, and many other forms of engineering. But this is a more ambitious subject.

Graphical user interface builder(GUI)

A graphical user interface builder (or GUI builder), also known as GUI designer, is a software development tool that simplifies the creation of GUIs by allowing the designer to arrange graphical control elements (often called widgets) using a drag-and-drop WYSIWYG editor. Without a GUI builder, a GUI must be built by manually specifying each widget's parameters in source-code, with no visual feedback until the program is run.

Graphical user interface builders are often incorrectly called rapid application ... to wxDev-C++, Embarcadero C++ Builder and Microsoft Visual C++/MFC now.

User interfaces are commonly programmed using an event-driven architecture, so GUI builders also simplify creating event-driven code. This supporting code connects widgets with the outgoing and incoming events that trigger the functions providing the application logic.

Some graphical user interface builders, such as e.g. Glade Interface Designer, automatically generate all the source code for a graphical control element. Others, like Interface Builder, generate serialized object instances that are then loaded by the application

International Mobile Station Equipment Identity(IMEI)

is a number, usually unique, to identify 3GPP (i.e., GSM, UMTS and LTE) and iDEN mobile phones, as well as some satellite phones. It is usually found printed inside the battery compartment of the phone, but can also be displayed on-screen on most phones by entering *#06# on the dialpad, or alongside other system information in the settings menu on smartphone operating systems.
IMEI (International Mobile Equipment Identity) is a 15- or 17-digit code that uniquely identifies mobile phone sets. The IMEI code can enable a GSM (Global System for Mobile communication) or UMTS (Universal Mobile Telecommunications Service) network to prevent a misplaced or stolen phone from initiating calls

The IMEI number is used by a GSM network to identify valid devices and therefore can be used for stopping a stolen phone from accessing that network. For example, if a mobile phone is stolen, the owner can call his or her network provider and instruct them to "blacklist" the phone using its IMEI number. This renders the phone useless on that network and sometimes other networks too, whether or not the phone's SIM is changed.

Every GSM mobile phone has a unique serial number, called an International Mobile Equipment Identity (IMEI) number. This number is built into the phone's hardware by the manufacturer, not the SIM card which is supplied by the mobile carrier and can be removed and inserted into another phone.
The IMEI is only used for identifying the device and has no permanent or semi-permanent relation to the subscriber. Instead, the subscriber is identified by transmission of an IMSI number, which is stored on a SIM card that can (in theory) be transferred to any handset. However, many network and security features are enabled by knowing the current device being used by a subscriber.

integrated development environment (IDE)

is a software application that provides comprehensive facilities to computer programmers for software development. An IDE normally consists of a source code editor, build automation tools and a debugger. Most modern IDEs have intelligent code completion.

You can easily combine language support and other features into any of our default packages
Some IDEs contain a compiler, interpreter, or both, such as NetBeans and Eclipse; others do not, such as SharpDevelop and Lazarus. The boundary between an integrated development environment and other parts of the broader software development environment is not well-defined. Sometimes a version control system, or various tools to simplify the construction of a Graphical User Interface (GUI), are integrated. Many modern IDEs also have a class browser, an object browser, and a class hierarchy diagram, for use in object-oriented software development.is a software application that provides comprehensive facilities to computer programmers for software development. An IDE normally consists of a source code editor, build automation tools and a debugger. Most modern IDEs have intelligent code completion.
With its editors, code analyzers, and converters, you can quickly and smoothly upgrade your applications to use new Java 8 language constructs, such as lambdas, functional operations, and method references.(in Java)

Some IDEs contain a compiler, interpreter, or both, such as NetBeans and Eclipse; others do not, such as SharpDevelop and Lazarus. The boundary between an integrated development environment and other parts of the broader software development environment is not well-defined. Sometimes a version control system, or various tools to simplify the construction of a Graphical User Interface (GUI), are integrated. Many modern IDEs also have a class browser, an object browser, and a class hierarchy diagram, for use in object-oriented software development.

KNOW XAMARIN IN VISUAL STUDIO

Xamarin is a based softby the engineers that created Mono,Mono touch and Mono android  which are cross platform implementations of the common Language Infrastructure (CLI) and Common Language Specifications (often called Microsoft .NET).

ware company created
With a C# shared codebase, developers can use Xamarin tools to write native iOS, Android, and Windows apps with native user interfaces and share code across multiple platforms.Xamarin has over 1 million developers in more than 120 countries around the world as of May 2015

 Mono is a free and open source project led by Xamarin (formerly by Novell and originally by Ximian) to create an Ecma standard-compliant, .NET Framework-compatible set of tools including, among others, a C# compiler and a Common Language Runtime.

The stated purpose of Mono is not only to be able to run Microsoft .NET applications cross-platform, but also to bring better development tools to Linux developers.[4] Mono can be run on many software systems including Android, most Linux distributions, BSD, OS X, Windows, Solaris, and even some game consoles such as PlayStation 3, Wii, and Xbox 360.
 Xamarin for Visual Studio

Xamarin claims to be the only IDE that allows for native iOS, Android and Windows app development within Microsoft Visual Studio.Xamarin supplies add-ins to Microsoft Visual Studio that allows developers to build iOS, Android, and Windows apps within the IDE using code completion and IntelliSense. Xamarin for Visual Studio also has extensions within Microsoft Visual Studio that provide support for the building, deploying, and debugging of apps on a simulator or a device.In late 2013, Xamarin and Microsoft announced a partnership that included further technical integration and customer programs to make it possible for their joint developer bases to build for all mobile platforms. In addition, Xamarin now includes support for Microsoft Portable Class Libraries and most C# 5.0 features such as async/await. CEO and co-founder of Xamarin, Nat Friedman, announced the alliance at the launch of Visual Studio 2013 in New York.

VISUAL STUDIO 2015

 

Welcome to Visual Studio! We’ve got everything you need to create great apps for devices or desktop apps, for the web and in the cloud. Write code for iOS, Android, and Windows in one IDE. Get great IntelliSense, easy code navigation, fast builds, and quick deployment. Visual Studio increases your productivity and makes it easy to do your work alone or as part of a larger team.

Download Visual Studio Community for free to start coding right away. If you want to do cross-platform development, make sure that you install the optional packages. (You can get more features with other editions of Visual Studio.)

Jump right in, create a new project, and start writing code. Choose the type of app you want to create. Or you can take a tour of the Visual Studio IDE to get familiar with the tools.

And don’t forget to explore our code gallery to find samples to help you write your app more quickly!
 Extend Visual Studio

Add your own Visual Studio extension to include a tool or script that you often use while coding. You can create custom menu items and tool windows to integrate your own tools into the Visual Studio IDE. You can extend the Visual Studio editor to analyze and fix code, or add a new project type to include just what you need.

To find the latest version of the Visual Studio Extensibility Tools (VS SDK), see Visual Studio SDK.

You can use the .NET Compiler Platform (Roslyn) to write your own code analyzers and code generators. Find everything you need at Roslyn.

Find existing extensions for the VS IDE created by Microsoft developers as well as our development community.
Build apps for Android, iOS, and Windows

You can use Visual Studio to build apps for Android, iOS, and Windows devices. Learn more about it at Cross-Platform Development in Visual Studio.

For information about Universal Windows Apps (UWP), see Universal Windows Apps.

Choose the tools you need based on your app requirements and the language you want to use.

    Xamarin for Visual Studio: A common code base in C# for all devices

    Apache Cordova with Visual Studio: A common code base for HTML, CSS, and JavaScript or Typescript

    Visual Studio Tools for Unity: 2D/3D game development in C#

    C++ for Cross-Platform Development: Shared code libraries and apps in C++

    Visual Studio Emulator for Android : Visual Studio Emulator for Android: Debug and test your Android apps no matter the IDE

HOW DEBUGGER WORK IN PROGRAMMING

A debugger or debugging tool is a computer program that is used to test and debug other programs (the "target" program). The code to be examined might alternatively be running on an instruction set simulator (ISS), a technique that allows great power in its ability to halt when specific conditions are encountered but which will typically be somewhat slower than executing the code directly on the appropriate (or the same) processor. Some debuggers offer two modes of operation—full or partial simulation—to limit this impact.

 a debugging interface that allows debuggers and IDEs to debug managed code can do four main kinds of things (plus other things in support of these) to help you catch bugs in the act:

• Start your program, specifying anything that might affect its behavior.
• Make your program stop on specified conditions.
• Examine what has happened, when your program has stopped.
• Change things in your program, so you can experiment with correcting the effects of one bug and go on to learn about another. 

HTML5, Hybrid or Native Mobile App Development

Intro
Many organizations taking their first steps to implement a mobile strategy are facing an important decision that will influence the results of this initiative. The process of choosing a development approach for a mobile application, namely native, web or hybrid, entails many parameters such as budget, project timeframe, target audience and application functionality to name a few. Each approach carries inherent benefits and limitations, and finding the one that best addresses the organization’s needs could be a challenging task.
The purpose of this whitepaper is not to identify the best development approach, as such does not exist, but rather to list the pros and cons each carries and describe the different scenarios, or enterprise requirements, that best fit one or the other.

Introducing the Approaches
Native Applications
Native applications have binary executable files that are downloaded directly to the device and stored locally. The installation process can be initiated by the user, or in some cases, by the IT department of the organization. The most popular way to download a native app is by visiting an application store such as Apple’s App Store, Android’s Marketplace, or BlackBerry’s App World, but other methods exist and are sometimes provided by the mobile vendor.
Once the app has been installed on the device, the user launches it like any other service the device offers. Upon initialization, the native app interfaces directly with the mobile operating system, without any intermediary or container. The native app is free to access all of the APIs that are made available by the OS vendor and, in many cases, has a unique look and feel that is typical of that specific mobile OS.
To create a native app, developers must write the source code (in human-readable form) and create additional resources such images, audio segments and various OS-specific declaration files. Using tools provided by the OS vendor, the source code is compiled (and sometimes also linked) in order to create
an executable in binary form that can be packaged along with the rest of the resources and made ready for distribution.
These tools, as well as other utilities and files, are normally called the SDK of the mobile OS. Although the development process is often similar across different operating systems, the SDK is platform-specific and each mobile OS comes with its own unique tools. The following table presents the different tools, languages, formats and distribution channels associated with the leading mobile operating systems.
These differences across platforms result in one of the most critical disadvantages of the native development approach – code written for one mobile platform cannot be used on another, making the development and maintenance of native apps for multiple OSs a very long and expensive undertaking.
So why is it that in spite of this costly disadvantage, many companies choose to develop natively? To answer that question we will need to better understand the role of the APIs.