Ratings
These are extremely important because when someone lands on your app page it's the main thing they use to judge the quality of your app. A high rating and a decent volume greatly increase conversion. Unfortunately, there isn't too much you can take away from ratings, except that hopefully, you are trending upwards. Ratings prompts can be extremely effective in increasing ratings.
Reviews
Unsolicited feedback like this is extremely valuable to product teams. It can early alert on bugs and crashes, give you new product ideas, help you find advocates and much more. It's also really important to reply to negative reviews to both help the user and also ease concerns on potential new customers reading that review on the stores. Note that reviews are usually more negative then your ratings.