How to Detect Snooping in iOS Apps?

Question

I have the official Instagram app on my phone. Today I received a text message from a friend (SMS) wherein he suggested I joined a certain organization which isn't relevant for me at all. An hour later I open Instagram and see an add for this organization.Seeing how Im not at all their target audience, it made me suspicious. I know full well that one example does not make a case, so Im wondering if there are any tools I can use to learn more about the inner processes in Instagram?(did check app settings, it was mostly restricted except "Background App Refresh")

Nextgrid · Accepted Answer

There is no way Instagram has access to your texts on iOS.What most likely happened is that the friend searched for this organization, then looked at your Instagram profile and Facebook decided to take a gamble and check if you were also interested in it by showing you the ad and see if you'd click on it or look at it a bit longer.