In today’s market, all we know that the importance of mobile apps for companies to improve their business is high. No matter of what business it is, a mobile app can help them to get and retain the customers.
Recently I was exploring on available frameworks for developing mobile apps to iPhone, Android and Windows Phone. As a .NET programmer, I was end up with building the apps for Windows Phone device.
In this article, I would like to share my knowledge and experience on developing apps for Windows Phone.
In order to develop apps for Windows Phone you need to have developer account ($19/year for individuals and $99/year for company). If you don’t have the developer account, you can only register one windows phone for app development. But in order to publish your apps to Windows Phone Marketplace, you must have a developer account.
What you Need?

Visual Studio Express 2010 for Windows Phone (apps targeting Windows Phone 7.x)

Or Visual Studio Express 2012 for Windows Phone (apps targeting Windows Phone 8.x)

Windows Phone / Windows Phone Emulator

Zune Software (for establishing communication between Phone and Computer)

Windows Live ID

What you should know?

C#/VB.NET

XAML

Silverlight/WPF Controls

Windows Phone SDK

Microsoft Expression Blend (optional)

HTML5, CSS3 and JavaScript (when using Apache Cordova Framework)

Developer Tools!
In order to develop the apps for Windows Phone, you must install the Windows Phone SDK. Using SDK developers can build native apps for Windows Phone.
You can get the Windows Phone SDK from here:
http://dev.windowsphone.com/en-us/downloadsdk
Windows Phone SDK comes with following main tools:

Visual Studio Express Edition for Windows Phone (VS version depends on SDK version)

Windows Phone Project Templates

Windows Phone Emulator

Windows Phone Developer Registration Tool

Windows Phone SDK Assemblies

Silverlight SDK

Microsoft Expression Blend

Microsoft Advertising SDK

Register Windows Phone for Development
Sometimes you need to test the app on physical device instead emulator. In order to deploy and test your app on physical device you must unlock the phone for development. To register the phone for development you should use ‘Windows Phone Developer Registration’ tool which comes with Windows Phone SDK.
First connect your windows phone device to computer using USB cable. When it is connected Zune software automatically launches. Once Sync has been completed (check Sync status on Zune’s phone summary page), launch ‘Windows Phone Developer Registration’ tool. You will see a Register button on the window. Input your Windows Live account username, password and click on Register button. If your phone registered successfully then you will see a screen as shown below:

 
Start building app!
Developing apps for Windows Phone are as simple as you developing applications using Silverlight or WPF technology. Now we’ll discuss the step by step procedure on building our first app.
Launch Visual Studio -> New -> Project -> Silverlight for Window Phone -> Panorama Project Template
Note: Windows Phone SDK integrates set of project templates in to your Visual Studio for developing apps for Windows Phone. In this article we will use one of the project template called Panorama app template.

 
Once you have created a project, you would see the most of readymade pages and sample data model which needed to run the app. Among them,
App.xaml provides you to take the control over the life cycle of application, where most of the application level events to be registered. In this file you can tell to the application when to bind the data model, when deactivating or activating the app what should be happen and even we can create local database, etc.
MainPage.xaml is the initial screen of your app. You can change initial page to any other in application manifest file. When you open any of XAML page, it looks as below:

 
Windows phone SDK comes with many of default controls and these controls are morethan enough to full fill any requirements.
In case the default controls are not enough for you and want to see more enhanced controls, you can download and use Silverlight and telerik controls.
Silverlight controls (free):
http://silverlight.codeplex.com/
Telerik controls for Windows Phone (30 days free trial):
http://www.telerik.com/products/windows-phone/overview/all-controls.aspx
Windows Phone SDK comes with set of phone libraries, using that you can talk to the phone and easy to implement native features.

 
Testing your app?
You can debug or test the app either in Windows Phone Emulator or physical device. If you want to test the app on physical device, your phone must be register for development as described in one of the above section.
In order to test the app, first select the target device as shown in below screenshot and run the application. Every time when you run the application, the old app on the target device would be replaced with new build and automatically launches your app.

 
Publish app to marketplace?
Every time when you build the app, Visual Studio creates a distributable package called XAP package. You can install this XAP package on any other Windows Phone device which meets the SDK version requirements.
If you want to make your app available to globe, you must submit the app to Windows Phone Marketplace/Store. But your app must meet the app submission requirements and also your Windows LiveID account must be a registered developer account for submitting apps.
 
Isn't so easy to build apps for Windows Phone?
Be proud to be a Windows Phone Developer..! Cheers…!