I'm writing this with a little bit of frustration. I think there really should be a set of media components built in to Forms.
Last few days I've been working on a pretty simple app that requires an basic MP3 player with custom graphics, earlier I've used my own Dependency files for this, but in this particular project I got problems with Android and my old solution so I thought I move it over and do it all in Forms and then using XamarinMediaManager that everyone suggesting, and here is what I see as a big problem, this plugin probably worked great before but that's not the case anymore and the developer answer most questions with that he don't have time anymore to update it.
This makes Forms very fragile, when you count completely on independent developers of such basic functionality as playing media in a app. I love the idea that developers can make additions to Forms, but the most basic must be in the core.
I solved it for now with SimpleAudioPlayer instead but I really hope to see this inside Forms in a near future.