>In this paper, we present a study of 24k Android and iOS apps from 2020 along several dimensions relating to user privacy.

>We find that third-party tracking and the sharing of unique user identifiers was widespread in apps from both ecosystems, even in apps aimed at children. In the children's category, iOS apps used much fewer advertising-related tracking than their Android counterparts, but could more often access children's location (by a factor of 7).

>Overall, we find that neither platform is clearly better than the other for privacy across the dimensions we studied.

Well, here's a novel idea: don't get children their own smartphones, uninstall/disable all apps bar the essentials, and keep your own usage to the bare minimum.