As has been mentioned a few times: When Digg fucked up, reddit existed as a growing but small competitor. Reddit has no such competitor.
Anyway, for many, the competition is "nothing at all". I will never download the official Reddit app. It's that bad. The mobile experience is worse. I'll just find something more productive to do with my time.
Yes, this is what people miss about Twitter too. They scoff at Mastodon, for example, and of course Mastodon is unlikely to ever attract hundreds of millions of users, but the biggest "competition" to Twitter is simply disengaging from Twitter. Quitting, not switching. You don't have to be on any social media site; you can spend your time in other ways.
I like to consume text content in public transport. Unfortunately, Reddit is like the worst app possible with bad/interrupted connection. Even a real-time strategy game I'm playing that needs constant data exchange works better in the subway than reddit.
At least they stopped forcing you of the mobile version onto the app.
The official mobile app is just inexplicably bad. The other day I was browsing through the 'Popular' tab, and every time I clicked on the thumbnail for an article, it took me to the web page... of some other article. Completely unrelated as far as I could tell. Tap on a CNN article about Trump indictment, instead get an EW article about Gwen Stefani (or whatever, I don't remember what it was).
It was consistent, too. Every article went to a different article instead, but tapping on that article always gave you the same different article. Tapping onto the comment screen and then onto the article gave the correct article.
A few weeks ago, the problem was different; I would tap on an article, and it would load up some other article, and then also the article I was trying to read. I'd read it, close it, then have to close the other article, then I'd be back at the main list.
For the longest time, refreshing an article list would result in a bunch of broken-looking entries in the list view; entries without titles, titles overlapping images, entries that were too big, and so on. Refreshing again often fixed it, but then gave me a new set of articles as if I'd already read the messed up ones it had brokenly tried to show me. This used to happen every single time; then it was just sort of random, about 50% of the time. I haven't noticed it lately because I got out of the habit of refreshing lists and I just kill the app when I want to get newer content.
There's also a little hovering downwards-arrow symbol to skip to the next top-level comment. It's black, it's fairly large, and it hovers over the content. You can't get rid of it whether you want it or not. The best you can do is toggle a preference that says "I don't want this to be movable", and then it sits in the corner, over top of the content, forever (except when it bugs out and sits in the middle of the screen on the left side forever).
For the longest time, the comment box to type your comment into was a fixed size; if your comment didn't fit into two or three lines, then your text wrapped onto the fourth line or whatever, except the text box wouldn't scroll so you couldn't see what you were typing. I got in the habit of copying the text to Notes, writing my comment there, and then switching back to Reddit. 50% of the time, the Reddit app would reload and I would lose the comment that I was replying to, but the other 50% of the time I could paste my comment in and post it.
When creating a new post, you first put in the content you want (title, body, image, whatever), and then you hit 'Next' and choose a subreddit. It gives you a list of suggestions, based not on subreddits that you're subscribed to or post to regularly, but rather subreddits that you've engaged with lately. I saw a post from /r/doordash yesterday, so now the app is suggesting maybe I want to post there, or /r/Weddingattireapproval.
Note that some subreddits don't allow self posts, or don't allow image posts, but you have to create your post first before choosing a subreddit that maybe doesn't allow it, forcing you to go back and change your post type/content. This feature seems just generally really stupid.
It goes on and on. It's a genuinely horrible app which can rarely even get the basic functionality working, and bugs stick around indefinitely.
In all honesty I think Discord is the competitor. You can join dozens of communities under one login, lots of creators and studios set up their own server, set up a private server for friends, and there's more control over who can join and see content. I mostly use it to keep in contact with a couple of friends, so I bet there's even more that could be done.
<product review> site:reddit.com
There's a 90-9-1 rule of thumb ( https://en.wikipedia.org/wiki/1%25_rule https://www.nngroup.com/articles/participation-inequality/ ) and a migration from reddit to discord will benefit the 9-1 portions and provide a net loss to the 90% (lurkers / people who find content via google).
You can't make a community go somewhere. The the place that it ends up is on discord (and irc in times before), then discoverability for the rest of the population that aren't participants in that community will suffer along with the companies that previously hosted that content and were able to monetize their eyeballs.
... but isn't that what people have been wanting? "Down with {big corp}!" be it google or reddit or Facebook?
Their standing agreements with Reddit inc. may prevent them from doing so however.
None of the backends are likely able to support the load that Apollo (and RIF) would do (see also what HN did to Lemmy the other day).
Many of the users of Apollo and RIF are using them and the APIs that reddit was providing for free before to avoid paying for things and seeing ads making monetization of those and supporting the backends even more difficult (not that Lemmy and friends want to pay for server costs with advertisements - they'd rather donations - but that isn't a reliable income stream).
The thing is that most users of reddit and discord don't care about older topics. Go to any large sub with lax moderation and watch how many times the same questions are posted.
For many communities, it doesn't matter if its a reddit replacement with the reddit functionality but rather that it is a place to host that community (that will adapt to and complain about the confines of their new home).
It only lacks real functionality as a reddit replacement for those people who are lurkers and want to consume a digest of past content (and maybe add a forgettable comment to the end of a too long comment tree).