To share your review or another user's review, navigate to the title page and scroll down to "User Reviews" - then:
Select "See all user reviews", and scroll to the bottom of a review to "Report | Permalink"
Select Permalink for the review you'd like to share and you'll be taken to a page showing only this review. From here, you can copy the URL and send it around.
Tap the 3 vertical dots at the bottom right of the review and choose Permalink from the list.
You will be taken to a page showing only this review so you can share it from your mobile device.