Safari suddenly opening webpages as desktop view for iPhone

What is the deal with safari suddenly opening webpages as desktop view for iPhone users to have to go in and change that every time they open a webpage? I have read that it has something to do with iPads. I know I must be misunderstanding because I would rather switch the views on my iPad occasionally than on my phone constantly. Maybe it has something to do with the # of iPads in schools..

So my question I suppose is do I have it right and is there a solution?

[Re-Titled by Moderator]