How can I customize an iPhone first launch experience based on specific users?

I am trying to make my app automatically load specific content for a user upon the first launch.

For example, if a user is searching for information on product X via Safari, I would like to give them a referral to download my app in iTunes. 开发者_开发知识库After download, I would then like the app to automatically load screens relevant to product X without the user entering that info in themselves.

It seems that since apps are sandboxed they wouldn't have access to Safari cookies, as this would otherwise be the perfect solution. Any advice?

Altough it's very interesting concept, I'm afraid it's impossible. The only idea that comes to my mind is to:

1. Store device's ID when user visits your website as well as what page was visited before redirecting to the AppStore.
2. Waiting for user to download the app.
3. Querying your server for this data on application launch and then setting up your UI accordingly.

However, the device ID is not exposed through Mobile Safari and even if you'd find a way to get it, this action would definetly be considered illegal.