Apple has patented a new system that will help you avoid unwanted tracking. It creates an alternate identity which you pass off as yourself. Reported by Patently Apple, they explain it like this:

Imagine being on the internet or merely on a network, and someone's basically collecting information about you, and you're being tracked for a host of reasons. The cloning service from Apple will allow you to configure a "clone" of your identity which would be the one those interested parties tracking you would see.

You can also define a host of attributes about the clone, and when you want different parts of your real identity used. The reason these are clones and not outright fake identities, is that the clones would be designed to be similar to you in some respects so that whoever is tracking you won't catch on.

The tech does not pinpoint or specify anything and it makes it intentionally broad, but the whole gist of it is comparable to creating a dummy email account to sign up for newsletters you never read. [Patently Apple]