Amazon wants you to buy pretty much everything on its site, from shoes to ships to ceiling wax. But especially the shoes, at least with the latest update to the Android shopping app. It brings support for a new Amazon Closet feature, which is kind of like a Pandora recommendation system for clothing.
Closet appears to be an entirely new element of the mobile app, not to be confused with Amazon Prime Wardrobe. It's essentially a more targetted version of Amazon's buying recommendation system, which scans your previous clothing purchases to tailor (geddit?) recommendations based on your personal style, price range, and presumably other factors.
I've bought a fair bit of clothing on Amazon, but it's almost entirely workout gear, so the outfit ideas that the app is generating are pretty much nothing except gym clothes. If you're not happy with the results based on your Amazon purchase history, you can manually add clothing items from Amazon's store listings.
According to the changelog, Closet is available in the US only at the time of writing. You can find it in the side menu, under Programs and Features>See All Programs>Closet. (You may have to scroll down a bit.)