In order to remotely help family and friends with iOS devices get a decent xmpp app up and running, I put together a few screenshots of the settings one needs to check after setting up an account in Siskin.
Frustrating that these need to be checked (including "enabling" the just-set-up account!), but once these setting are in place it all seemed to just work ...after restarting the iPhone (the good old "turn it off and on again").
Delivery is prompt, and voice and video calls between Conversations and Siskin work great too!
It's pretty rough, but I don't really have access to iOS devices so it's the best I've got.
Yes, they are. We've even removed many of the "essential" ones so they can't be disabled by accident.