@Smokindog when the developers for the different client devices are able to add the grid view to their platform it will be released. Sorry but really have no other information to provide. I have not seen it on any of the client devices I use at this time either.
@MSplexBox not sure exactly what you are asking here so guessing you have not seen the interface yet.
Home screen when you access Plex. Can access the grid view for Live TV under the Live TV & DVR, or watch already recorded content using the Recently Added sections, or by navigating into a library of all recorded content separated by content type (TV, Movies, Music, etc.)
Screenshot of grid view for Live TV