Finding Cached Data?

Hi everyone,
I’m just curious about caching. I’m about to finally release my app again after it’s been down for such a while. I’m working on editing my Terms of Services and Policies whereas I’m explaining how my service doesn’t cache their information but their devices possibly could. I want to prove to myself and see which kind of information is/could be getting catched.

Is there any way to display cached data?
Is it only available to devices that’s registered the data?

  • Messages
  • Friends
  • Profile Photos
  • Sent Photos
  • Emails
  • Etc.

I’m offering an instant messaging app and I refuse to cache anything. Period.

I want to understand if my mind is clear:
Let’s say, there’s a device that’s never messaged this user could we load the other user’s profile photo, friends, messages, etc.?
Or –
Are they only accessible to the ones the user caches also?
Like, interceptions.

I want to forbid them from searching a deleted user and their profile photos or data being displayed.
I understand cache but, I don’t understand if it’s globally accessible.

Tip: It’s not Base64, that’s forever… Ew.