True but looking at my own iTunes App Analytics dashboard for example, about 50% of users don’t opt-in to share analytics with us. At Facebook-scale 50% means

True but looking at my own iTunes App Analytics dashboard for example, about 50% of users don’t opt-in to share analytics with us. At Facebook-scale 50% means at least a billion users will still opt-in, but probably significantly less than what they were tracking before at the 100% level.