Yesterday I changed all commas to semi-colons on this course:
https://www.memrise.com/course/401660/floral-identification-plants/1/
so that the alternative spelling of a few flowers would work without setting up alternatives.
The Android app is still showing commas!
How long does it take for the course versions to be the same?
you might need to log out and back into the app for the changes to come through, for me this normally updates the courses
Thanks - I would have thought the course should be updated not my window on it.
Yes that worked thanks! 
I would agree, my expectation would also be that the app notices that there have been changes, and updates its local cache. alas…