A Finnish analyst has got together some facts and figures which he thinks proves that Android will kill off PCs.

Horace Dediu said that iOS and Android devices are considered to be substitutes for personal computers and the PC market is going to collapse. Dediu runs Asymco which sells software development and consulting services for companies interested in deploying mobile applications. However he has come up with a lot of numbers and graphs to prove his point. His rise and fall of personal computing compares PCs to Macs, iOS and Android devices in shipped units and market share.

He claims that smartphones are being integrated into the personal computing space and we are writing on them rather than our PCs. Dediu admits that his views are a bit extreme. It assumes that there is no competition, but it does show how things work as a historic pattern.

His figures show that starting around 2007, when Apple (AAPL) introduced the iPhone, sales of devices running mobile platforms have eaten into a large portion of traditional desktop and laptop sales. Dediu lumped Apple products together in this graph and Android devices are all mobile devices by looking at these figures it is possible to see how many are out there. There were 352.8 million PCs were sold worldwide in 2011 but Samsung alone thinks it will sell 150 million smartphones next year.

Some of this is due to poor economic factors, but if Dediu is right then The bad economy is actually helping create a perfect storm in favour of mobile devices. They’re a cheaper starting investment for consumers, they have connectivity to the growing number of cloud services, and they meet many needs that used to be fulfilled only by PCs.