If the filter detects that the content has been requested by a web service it passes back the content from the "alternate content" field. Its up to the template author to create appropriate content in the "alternate content" fields. Right now I am using this to fall back to standard HTML5 audio and video tags, from the fancy players (VideoJS, flowplayer,"3 speed audio player", etc).
After thinking about it, I find it hard to see how the mobile app could ever handle some of what Generico/VideoEasy/PoodLL could pass to it. So I added "alternate content" fields to each of those filters.