Seriously. Stop.
Apps allow far deeper and richer access to various data structures than what should be allowed; this has been proven time and again since mobile OS existed, I think both Apple and Google are to blame for ever allowing developers to freely access whatever they wanted, whenever they wanted, to upload it to any server, without any transparency or oversight (and that's a huge problem on Android, still).
If you can, use the browser (the new Firefox for Android is quite good), which at least limits your exposure to these third parties accessing information they should not.
old.reddit works okay in the browser, I am not so sure about LinkedIn as I don't use it. These days I just rely on using TOR for things like email, Protonmail has a .onion address which is a nice bonus.
I carry very few apps on my device, and I make an effort to exclusively use those found on f-droid, open source, not many permissions.
It's the biggest perk of Android; you can use any store you like, and most APKs install absolutely fine. Disable Play Services and various other tweaks and you're okay.