Google has been asking searchers randomly to rate the web search results for as long as I can remember. But I've never seen anyone report or notice Google asking mobile searchers to rate the search results.
Today, while testing to see if the mobile friendly label was live yet or not, I noticed while in Safari on my iPhone 6 running iOS 8, Google asked me to rate the search results.
Here is a picture of what it looked like and of course, I gave it a five star rating:
Have you seen this on the mobile results before?
Forum discussion at Google+.