The new iTunes connect has analytics features now. You can specify the provider (pid) id and campaign id (cid) in the url. e.g.
https://itunes.apple.com/fr/app/candy-crush-saga/id553834731?mt=8&pid=1234&cid=My_Campaign
Can you pass those values into the app for various purposes?
I could not find anything that points to that, even after checking:
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
ref:
http://www.applift.com/blog/new-era-attribution-analytics.html
Unfortunately these params are not passed into the app. They are only used for iTunes Connect stats.
Here are the two common workarounds:
Using a fingerprint to implement deferred deep link and passing the params through that link (Tapstream can do this).
Using a provider like Tune/MobileAppTracking to match the link using the ID for advertising (IDFA).
I wrote a blog post to explain the details: https://attributionapp.com/blog/lets-solve-ios-attribution-methods/
I will edit this response in the future if Apple changes their API. If you let Apple know what you want to build and why passing in the params is a better policy they might change their minds faster: https://developer.apple.com/contact/