I know this is an old thread but I just ran into the same problem on my iPad. Here’s how I solved the problem. First, whatever browser you’re using, in my case it was Safari, make sure you’re signed into whatever provider is linked to your Bungie account. I opened a new window in Safari and went to PSN and signed into my account. Then I went back to the companion app and signed in. Instead of an error notice, my PSN ID came up and I just clicked on it. Hope this helps someone.

[b]Bungie Companion app > Playstation sign in page > Help/Site Map > Playstation website/app > Sign in > Return to Bungie Companion app > Accept[/b] I found a way past the (A connection to the server could not be established) problem: I clicked on the option below the password input box which says 'Help/Site Map', this took me via the Bungie Companion app to a page which had the Playstation logo at the top rather than the Bungie icon. On this page, I clicked the 'Sign in/Create new account' button and entered my Playstation email+password here. I'm not sure if this worked because I already have the Playstation app on my phone or if the Bungie app was allowed to navigate to the Playstation website itself, so try downloading the PS app if it doesn't work for you. After doing this, I reopened the Bungie Companion app and it told me I was signed in as myself, with a page that said 'Not you? Click here' After pressing the 'Accept' button highlighted in orange below this prompt, I was successfully signed into the Bungie Companion app. Hope this helps! From companion app > Playstation sign in page > Help/Site Map > Playstation website > Sign in > Return to Companion app

Bungie Companion app > Playstation sign in page > Help/Site Map > Playstation website/app > Sign in > Return to Bungie Companion app > Accept I found a way past the (A connection to the server could not be established) problem: I clicked on the option below the password input box which says 'Help/Site Map', this took me via the Bungie Companion app to a page which had the Playstation logo at the top rather than the Bungie icon. On this page, I clicked the 'Sign in/Create new account' button and entered my Playstation email+password here. I'm not sure if this worked because I already have the Playstation app on my phone or if the Bungie app was allowed to navigate to the Playstation website itself, so try downloading the PS app if it doesn't work for you. After doing this, I reopened the Bungie Companion app and it told me I was signed in as myself, with a page that said 'Not you? Click here' After pressing the 'Accept' button highlighted in orange below this prompt, I was successfully signed into the Bungie Companion app. Hope this helps! From companion app > Playstation sign in page > Help/Site Map > Playstation website > Sign in > Return to Companion app

I’ve been in the same boat for a while on my iPad.