It's worth inspecting traffic from iOS apps. I normally do this by creating a wifi hotspot in Linux, connecting my iPhone to it, and then inspect the traffic with Wireshark. Then I look at the DNS protocol and what is listed there. There is so much tracking going on behind the scenes in apps it is staggering! Also some (not most) of the traffic is unencrypted and I've even seen stuff that was sitting in my pasteboard being uploaded to some random server. (Even popular apps like TikTok spy on the pasteboard)[0]

https://in.mashable.com/tech/12219/tiktok-and-other-popular-...