I had been using “Ok Google” on my Samsung Galaxy S6 when I noticed it had stopped working. It only worked in the Google app itself. So I did a search on the internet and indeed it appears Google have removed the functionality at their end.

There are lengthy threads on XDA and Google Product Forums, links below. Have you been affected and perhaps you have found a solution?

Additional sources – Google – https://productforums.google.com/forum/m/#!msg/websearch/xGiV6D4PMS8/Askz3-LqvVgJ

XDA Developers – http://forum.xda-developers.com/galaxy-s6/help/ok-google-detection-t3085435