In version 1.8, Roon Remote for Android smartphones lacks the ability to display and assign ratings (heart icons). Up to now, this was also possible for individual music tracks, now it is only possible for the entire album. The rating on a PC with a large screen is still possible. But in my opinion, the rating when using the smartphone is very important! Because that is the typical application.
It is possible (3-dots menu of track, top right).
Three dots bottom right 
on the now playing screen.
That’s right, thank you. But up to version 1.7 the ratings were continuously displayed together with the album titles, so I could immediately see which titles I had already marked and which were interesting for me. The function of only playing the well-rated titles is not a substitute. I would like the previous display type back.