As Skype started to push video calling to its mobile application I think this purchase is to get rid of competitors.

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Skype released Symbian version of their voip/video chat software. Symbian is operating system of most of the Nokia smartphones and have a very big market share. If you have a Nokia phone with Ovi store installed you can check it from there to see if you can download it. I personally use Skype to make cheap international calls from my mobile phone and as it explained official video below it could save you quite a bit of money.

More at Nokia press release