I only have Win10 handy right now, but the built-in "Reader" app there has an option for fitting a single page, two pages side-by-side, and continuous vertical

I only have Win10 handy right now, but the built-in "Reader" app there has an option for fitting a single page, two pages side-by-side, and continuous vertical pages. It's missing an automatic option to fit the page width-wise, which is what I'd prefer, but zooming in to that level is easy enough with the "+" zoom button overlaid in the bottom right corner. Not sure if that's a lot different than the Win8 version. It's been a while since I've used 8 now.