Lemmy is part of the Fediverse, a network of interconnected social media platforms. Lemmy is intended to work like Reddit, but instead of one central site, there is no central site. Instead, there are many different sites (nodes) that talk to each other.
Think of this like email. No one "owns" email. Instead, there are many email servers. Some are large, like Gmail. Some are smaller, like the email server that runs email at your work. And some people run their own email server, just for themselves.
Even though there are many different sites providing email, it does not matter which one you pick. For the most part, any email provider you choose can email any other.
Federated sites work the same way. Lemmy.nz is one site, Lemmy.ml is another. Beehaw.org is yet another. There are many different Lemmy sites, large and small. All these sites have their own users, they have their own communities (subreddits), and they all connect to each other. If you want to view posts on asklemmy on Lemmy.ml, you can subscribe. It doesn't matter which server you signed up to. You can comment on posts, upvote posts, the whole shebang. Regardless of which server you signed up to, you can seamlessly interact with posts, comments, and upvotes across the entire network.
Hopefully this answers more questions than it raises, but really it could go either way. Reply to this post if you have questions (regardless of which server you signed up to).
Sorry I don't use iOS, but in theory it should be no different than any other instance. Hopefully someone else can comment on their success ( or lack of).
But was there an error message? Did you write the server in full (i.e. https://lemmy.nz) or did you just write "lemmy.nz"? Whichever you tried, maybe try the other?
The web frontend uses websockets to connect to the API, which can fail to connect. If that happens, the page will load but things like logging in won't work.
I'm not sure why that would affect an app though, which calls the API itself. Unless the API itself wasn't working, but it is because it works for everyone else!
It's a shame no one else has responded, it would be good to know if it's a problem only for you, or for others as well.
I have found my issue - it seems that having a really long password (64 char) just won't work. I remember seeing an issue with Beehaw.org and long passwords, so I thought I would try it out.
Seems it has fixed it for both just the lemmy-ui frontend AND the app.
Well it could either be the long password or a specific symbol, haven't tested that far. In any case a 20 char password has allowed me to login to both Mlem and just lemmy.nz on Safari :)
Well done working it out! It's giving me flashbacks to legacy systems from a couple of decades ago that had 12 or 16 character password limits. I think hotmail was one of them. But they didn't tell you, they just cut it off behind the scenes so you didn't know most of your password wasn't being used!
Yeah it was a bit of trial and error getting to the solution! Wasn’t helped by the fact that I use a password manager that obviously pastes the password in - and they said in a GitHub issue that the Lemmy-ui front end truncates anything after the 60 characters, so wouldn’t have seen the issue as I wasn never typing the password in!