I used Reddit Is Fun for over a decade. It made Reddit usable on mobile for me. The UI for the mobile site and the official app make poor use of screen real-estate, IMO, and are designed to force you to continue scrolling and scrolling and scrolling. They're attention vampires.

RIF and other third-party apps had much cleaner UIs, that made it easier to find the content I was actually interested in, hide content that I didn't care to see, and interact with comments in a way that made sense for me. It was also easier to customize my notifications so that I would only be alerted by things I cared to be distracted by.

Without the third-party apps, I've reduced my Reddit usage tremendously. I used to spend probably a few hours a day just reading through Reddit, but now that I can't do that from my phone in a way that works for my use-case, I just simply don't use Reddit as much anymore. I only ever access it from my laptop now, and I only ever use my laptop while I'm on the toilet.

My Reddit use has been reduced to literal shitposting. Fuck Spez.

As one of the most active moderators across multiple subreddits for the past couple of years, I could only Moderate on my iPad because of Apps like Apollo.

Apollo worked, and it worked well. Where as Reddit’s Official App is broken more than it works and until very recently didn’t even have many of the core moderation features you would want.

A laptop on the throne? That's a new one. I'm usually escaping with just my phone and pretend flushing. Hehehe

A big thing to bear in mind is that Reddit has been around since 2005, but has only had an official app since 2016. For context, the first Facebook app came out in 2008, and while Reddit certainly wasn't that big at the time, it's still weird that it took so long to actually get an official app out there. More over, Reddit didn't start from scratch. They bought up the Alien Blue 3rd party app, which was the top dog on iOS at the time, and reworked it into the official Reddit app.

The point here being that, for a very long time, 3rd party apps were the only reasonable way to browse Reddit on mobile. Even after the official app came out, Reddit themselves stated there was no intent for 3rd party apps to go away. For a lot of us, those 3rd party apps simply were Reddit on mobile.

To more directly answer you question though, I used BaconReader for 11 years on Android. BaconReader still to this day has a slew of customization and tweaking options that the official app just doesn't have. Even simple features, like color coding the left edge of comment blocks, thereby making it much, much easier to keep track of where comment threads diverge. These things also weren't limited to BaconReader, as most 3rd party apps came to the same conclusions: there's pretty simple ways to improve the Reddit experience by just offering a few extra options and thinking a bit about how people use the site.

BaconReader was light, fast, barely used any data, and just worked really well. By contrast, the official app just... doesn't feel all that well put together. The basic usability options everyone else figured out years ago aren't present, the app is more than double the size of what BaconReader was, it positively guzzles data, and while there's lots of updates and feature adds, none of them do much to actually enhance the experience of... you know, browsing and interacting on Reddit. For me, the official app really isn't any better than just using a web browser on my phone, and that certainly uses less data and is less fussy, so that's what I use now. Certainly cuts down on just endless scrolling though.