The day the world was awakened to the sense of touch, writes CHRIS HORN

WHERE WERE you at 5.42pm on Tuesday January 9th 2007? That day joins other key dates on which the computer industry fundamentally changed.

Another such date is May 28th, 1936, when Alan Turing published his seminal paper proving that a machine could solve mathematical problems. On June 21st, 1948, the first real implementation of Turing’s hypothetical machine ran the first stored program. On April 20th, 1957, the software industry was born when the first high- level program was run. On October 29th, 1969, the internet was born as the first ever Arpanet message was carried. On August 6th, 1991, the first website went live, and the worldwide web was born.

So what happened on January 9th 2007?

Three new products were launched that afternoon: a widescreen music player with touchscreen controls; a revolutionary new mobile phone; and a breakthrough internet communications device.

But were these really as significant as the first computer, the birth of the software industry, the creation of the internet or the invention of the world wide web? Absolutely. The metamorphosis was their integration into a single device, as Steve Jobs chose that moment to announce: “Today we are going to reinvent the phone.” Apple had begun developing the iPhone in 2005 based on earlier work on what subsequently become the iPad tablet.

The personal computer – whether a desktop or laptop or notebook – is too large to permanently carry around. It sits awkwardly in your home office or bedroom, slobbering cables, keyboard and mouse. If you want to use it, it ponders its navel for an eternity before it is willing to respond to you.

So: is a personal computer sufficiently personal?

The smartphone and tablet have jolted the entire computer industry to its core. You tap, point and pinch: no more awkward mouse or keyboard. You can carry one in your pocket, hand or bag. It has a great camera, including video. It obsoletes a sat-nav and, now, with speech recognition, you can literally ask it anything, and it does a pretty good job in understanding you and helping out. Most of all, it responds immediately: and therefore has become a catalyst for impulsive shopping, especially from home.

With the smartphone and tablet, many more people have been brought online, many – particularly seniors – for the first time. PCs brought computing to the committed, but smartphones and tablets have brought computing to the community.

Thus any new start-ups which are solely and unconditionally committed to the smartphone and tablet are potentially enormous threats to the established players.

For the operators of telephone networks, the introduction of smartphones and tablets has dramatically increased the volume of data transmitted, making their traditional voice-based telephone traffic a small percentage of their overall wireless services.

In turn, this has made operating a mobile phone network more complex, causing the operating costs of a network to rise at a faster rate than the revenues it generates. Web-based advertising has had to be reconstructed to exploit the high-quality colour touchscreens. Marketing can now be segmented based on the actual locations of consumers. The publishing industry has been convulsed by e-books on tablets. Broadcast television is struggling to understand the implications of watch-anytime videos and films.

For software developers, the emergence of the web in the 1990s led to “write once, run anywhere” programming languages and toolsets. These same techniques can of course be used, and are being used, with smartphones and tablets, but the issue has become one of aesthetics. Your software may indeed be written once and can run anywhere, but does it continue to look really good on each specific tablet and smartphone? Does it behave well with a touch-based input, including in particular the various human interface widgets native on that device ?

For corporations, smartphones and tablets have led to frantic activity to build software applications and ensure their brands appear cool and accessible. The rise of community applications, social networking and gaming, alongside corporate applications, is leading to another problem: how do I quickly find the right “app” for what I want to do right now with my device? This search problem is new and may challenge the established players in web search.

The excitement of the IT industry, for those of us who work within it, is its periodic immense changes. Each change creates substantial opportunities for innovation, and enables new companies to challenge established ones. Right now, app development, mobile enterprise integration, re-architecting of mobile operator networks, mobile search, mobile augmented reality and many other areas are providing prodigious opportunities to build great new global companies.