When Google searching on a small screen, the part of the result that shows you a page URL isn't always very helpful. Anything but the top-level domain will probably be truncated. Especially within familiar sites, the mixture of page title and shortened URL may leave you unclear what part of the website you will navigate to once you click. Google is making a subtle change to clear things up. Let's jump straight to the example images:

domain_replacement_before domain_replacement_after

Left: old way, right: new way

If you're not seeing it, look at the green text below the large blue text. You're seeing both aspects of the change, which is that it displays both the name of the site rather than the URL and the breadcrumbs. This food-inspired term is for the way it shows you that the top result is the history page within the company section of the about area of Google. If you were looking for your search history from Google, you would immediately realize that this is not the right place for that.

Here's how the same search results look on desktop:

history_of_google_-_Google_Search

Not only is there far more room for the URL, they also fit (in the gray text) the name of the site, which in this case is Google. Breadcrumbs and other structured data don't show up in this instance, though, which makes the revised mobile interface arguably more useful. Desktop search does support breadcrumbs in other circumstances, it just didn't work for this example for some reason.

As usual with Google, this will be a staged rollout. The site names portion will only be coming to US users (and not all at once) while the breadcrumbs will gradually appear worldwide. There's no APK for this because it is a server side change and is geared towards browsers.