Mobile Computing - evolution and current status

When people talk about mobile devices, what immediately comes up to memory is the mobile phone. The mobile phone appeared after a sequence of about 100 years of inventions, which aim was to be able to communicate from a long distance.
The first successfull telephone transmission was accomplished by Alexander Graham Bell in 1876. He and Thomas Edisson competed in the race that lead to the invention of the first telephone.
Immediately in 1877 the first commercial telephone line entered into operation.


The mobile phone only appeared nearly 100 years after the first phone, adding mobility to the initial goal of speaking at a long distance.
The first (analog) mobile phone appeared in 1960. It was too big to be transported personally, so it had to be installed in vehicles.
In 1973 appeared the first handheld mobile phone (analog).

Only in 1977 appeared the first digital cellular networks.


Currently, mobile devices, including most mobile phones have processing power, having added the goal of mobile computing to the previous goals of distance communication and mobility.

Today, in a confluence of different lines and different research goals, we have IP phones (VoIP), cellular packet switching networks (3G, 4G), mobile devices of various sizes, manufacturers, and with different operating systems, incorporating sensors, GPS , electronic compass, accelerometer, etc.. 

The number of mobile subscriptions rose from just over 1 billion in 2002 to almost 5 billion in 2008. We currently have 6.8 billion people worldwide, and more than 5 billion mobile subscriptions, of which 50% are prepaid. 

First Windows Phone App

In this article we make a first approach to software development for Windows Phone.

To start, we need to install the Windows Phone SDK 7.1, wich comes with a free IDE (Visual Studio Express) and with a Windows Phone Emulator, which allows you to test your apps before deploying them to a Windows Phone-based mobile device.

In this example app, the Visual Studio 2010 has been used, but, of-course, Windows Phone SDK 7.1 must allways be installed.

Windows Phone execution model

Before starting the development of our first app, just some words about the Windows Phone execution model:

• Just one App may run in foreground at a given moment in time;
• Other Apps in execution are put into a dormant state;
• When the device's memory isn't enough, the operating system (OS) starts terminating Apps in the dormant state.
• Through their programming framework, Apps can manage their state when they are activated or deactivated. This can be used to give the user the impression that an app has always been running, even when it is stopped and later reactivated.

Create the Windows Phone Project

 In Visual Studio (or Visual Studio Express), create a new project with the template for "Silverlight for Windows Phone", and type Windows Phone Application: