With the Facebook and Twitter apps (and iOS apps, in general), they have complete control over how the network call is being made — and the referer makes it to

With the Facebook and Twitter apps (and iOS apps, in general), they have complete control over how the network call is being made — and the referer makes it to the server (for the post part.) One would imagine Pinterest would want to maximize this number. I'll try posting the referer detector to some more native apps and see what happens.