Apps accessing data and domains when not in use

Why would an app, in my case many apps (not ones that comes pre-installed) be frequently accessing data and domains when not in use and not open?

For example, Photoshop express has been accessing my photos every 30 minutes, every day. At this moment it accessed my photos 9 minutes ago and 45 before that. I haven’t used the app for at least 48 hrs. I haven’t taken any new photos in longer. What would be the possible reasons for this? Also just to mention, I have approximately 10 photo editing apps and pay for premium access to several, yet Photoshop express is the only app that is doing anything like this. It's actually the only app on my entire phone that is accessing data in a way that does not make sense. With the only other exception being my apple watch, which looks to be accessing my photos consistently once every day. The only reason this is odd is because I haven’t turned on or used my apple watch in probably 2 years, though it is still connected to my iphone.

I understand how to give and rescind an app's access to my data. I am not asking how to or how to not give any app permission to access anything. I am asking why an app would be doing something like that. I understand also how to ask an app developer directly for an answer and I suppose at a point I may. I am not asking how to ask any specific app a question about the usage of my data or the accessing of my data. I am asking what the possible reasons could be for accessing my data so frequently when not in use. I am asking here as opposed to directly asking an app, as this is perhaps the one example of this specific peculiarity, it is one among dozens when taking into account my next example found below and considering the amount of app developers I would have a direct question to ask. The time consuming nature of that inquest is not at all appealing as I'm sure one could imagine.

The aforementioned next example, which has many specific examples of said behavior though I’ll just mention the one. I have an app, depop, which has no access to anything according to my device. I have not opened or used this app in several months, maybe 3-4. Yet in the past 7 days this app has accessed 10 domains. I understand that limiting access to data is not limiting access to domains and that those are seperate things. I just thought it might be worth mentioning. I am just wondering why an unused and unopened app would be accessing domains at all and what the purpose of this might be? As far as I know, there is no way to modify an app's ability to access domains? Is that correct? I am fairly unfamiliar with this, outside of understanding that an app may access a domain if you click on something within the app or to create a profile or to use Siri perhaps. I am not familiar with any reasons an app would do this without ones direct engagement with said app.

Thank you for any help provided!