* <tt>url</tt>: A URL representing the root of a domain, without a trailing slash (e.g. <tt>"https://someapp.com"</tt>), is conventionally defined to represent "a web application"; URLs rooted further inside the site are conventionally defined to represent "in-application purchases", and can use whatever path scheme is convenient to the developer and issuer of the receipt. Currently the following URLs schemes are supported: http://, https://, and app://(for packaged apps)
* <tt>storedata</tt>: A string that uniquely identifies this app or product for the verifier of the receipt.
=== the user field ===