Hilary Duff's "little secret" is a new song called 'All About You'

It was a mystery that gripped the world, but Hilary Duff has finally put everyone out of their misery by con­firm­ing that the secret is indeed a new single.

And that new single is called 'All About You'.

And that new single has some 'cover art' to go with it and you can see that above.

And that new single is 'premier­ing' in America at some point today.

And that new single was co-written by some people who know what they're doing when it comes to writing a new single.

So there we go.