I am creating an app that allows users to rate businesses (who are our customers). The businesses would like the user reviews to be cross-posted to their Google Business Profile in addition to appearing as an in-app review in our ecosystem. Does anyone know if there is a way to embed a Google-blessed widget in a mobile app that would allow posting a review to the Google Business Profile?
New reviews can only be created via Google Maps UI or the Google Knowledge Graph UI. The Google Business Profile APIs only support listing and replying to reviews (https://developers.google.com/my-business/reference/rest/v4/accounts.locations.reviews).
So the closest way to get directly to posting a new review would be via this URL pattern:
https://search.google.com/local/writereview?placeid=<PLACE_ID>
e.g.
https://search.google.com/local/writereview?placeid=ChIJj61dQgK6j4AR4GeTYWZsKWw