Access logs are almost useless for analytics these days... all they give you is the URL that was visited and some extremely rough idea what OS and browser the client is using (UA parsing is a hellhole).
You don't get any more detailed information (e.g. device class, screen size/orientation) from analytics logs.
Also, if you're using one of the free hosting providers (GH Pages and the likes) you're not even going to get access logs.
I wonder if you could use CSS media queries to collect additional data about device characteristics, by linking to different URLs at different breakpoints?
Like a breakpoint for portrait mode would set the background of something to an image that's just a 1x1 pixel. So when that resource is accessed, you know the request came from a device in portrait.
I guess it depends on how different browsers decide to access resource urls in CSS files. If a browser just downloads everything first, and then processes the media queries, then it wouldn't work.
You don't get any more detailed information (e.g. device class, screen size/orientation) from analytics logs.
Also, if you're using one of the free hosting providers (GH Pages and the likes) you're not even going to get access logs.