“Much of this data collection takes place after the phone is first turned on, before the user logs into an Apple or Google account, and even when all optional data-sharing settings are disabled.”
Both phones phone home about every four and a half minutes. Android sends more by volume. iOS collects more kinds of data. You can’t opt out on either, because the tracking starts before you even sign in. Apple sells privacy as a feature. The study says it is a slightly smaller leak.