All user reviews on the site can be rated. At the bottom of each review, it will include the question "Was the above review helpful?" and Yes or No buttons where registered IMDb users can cast their vote.
Via the app, you can tap the thumbs up (Helpful) or thumbs down (Not Helpful) icon to indicate your opinion of the review.
Once your selection has been recorded, you will see these options replaced with a line of text indicating whether or not you found the review helpful. You can also tap on the three dots to the right to see options to give your opinion on the helpfulness of the review, and also an option to report the review as a Duplicate, Inappropriate, Not Relevant, or for containing an unannounced spoiler.
Please note that "helpful" doesn't necessarily imply the review was "positive" or "favorable". A review can be helpful even if it is negative, because it can help readers decide not to watch it.
The aim of this feature is to highlight valid, well-written reviews at the expense of less interesting ones. We think that our users are ultimately in the best position to decide what's good or not for them, and that their opinion should be given consideration when displaying user reviews on the site.