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This may be a rooky question so apologies in advance if it is! A client of mine has asked why his site's rank is different when he searches for it from his iPhone or computer (where he uses IE) and also on Bing. Obviously I know that there will be differences between Bing and Google so I can explain that to him. But he seems to be implying that the different browsers are affecting the results on his iPhone and computer. I've tried this myself using Firefox and IE and on Firefox the site ranks page 1 but on IE it ranks page 3 (both using Google). Is this likely to do with the browser having information about my past search habits or is it actually the browser affecting the SERP? Again, sorry if this is a stupid question! Thanks in advance.