
There's always going to be a balance required between usability and privacy at the end of the day. I'd recommend not taking the nuclear option with this one and take some care as to which apps you disable it for. This is meant to enable those apps that do need to perform update and content checks to do so while you are not actively using them and so provide you with notifications and the like. I would also suggest disabling the Background App Refresh function which can be found in Settings > General for those apps that really don't need it. While you are in the privacy settings, you may as well turn off location services for apps that you don't want to be tracking your location.

It will also mean you'll see random adverts rather than targeted ones, but to be honest most of the "targeted" ads I see on any platform are pretty random anyway.

This will prevent advertisers from getting usage statistics including search history data. You can start by heading to the Settings > Privacy > Advertising section on your iPhone and enabling the Limit Ad Tracking function. Just don't expect to be able to stop all the spying, because that isn't going to be doable I'm afraid. If the question had been what you can do to limit the tracking problem, then things are somewhat more positive. So what can you do to stop the tracking yourself? Good question, to which the answer is nothing. More than one information security and privacy expert have already told me, in off the record conversations, that they think this is unlikely to be workable. Rumors are rife that Apple CEO, Tim Cook, will try and dampen the flames with an announcement tomorrow (June 3) regarding limiting these trackers when it comes to apps in the App Store "Kids" section. Especially in light of that "what happens on your iPhone." campaign. However, that doesn't mean that Apple gets a free ride.

Of course, it isn't just iOS apps that do this.
