Problems signing into my Twitter?

[Gareth]

I have a Twitter, and I've been signed in on my IPhone since I made it. But I can't remember the email address I used to make it. I can't sign in on anything else which is annoying. I copy out my username and use the password I'm fairly sure I set but it says, 'error they can't be authenticated'. How can I change my username or my password or retrieve the email address I used while only signed in on the IPhone app? Or just anyway to sign in on another device?

[Clive J]

Can you not simply create a new account. Do this on a computer and then use the details to sign in on your IPhone.