you can probably get the stats for the year 2012 within a few days from now as it will be carried out by some of the professionals, but it is not possible to get the stats for the usage in 2013, as it has not yet arrived, but yes, definitely one can anticipate more access of the internet from the mobile phone rather than on PC's.
I can't give you names but definately there are some companies that will write about the usage of internet in different devices. Look mainly for marketing companies specialized in online marketing or do a search in Google for internet usage analysis or infographics or something similar.
I would assume that hubspot would have some info or they will publish something soon.
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