No. They are two different protocols. The closest you could do would be to forward your pop3 email to an exchange account.
How would I setup the POP to forward through a gmail account? Could I do that?
IF the mail provider has a web interface to your mailbox, chances are there's an option in that web interface somewhere to auto-forward mail.
Can you go to a web site to read email for the account you want to forward from?
Absolutely!
As long as you also have the pop3 account (and its smtp counterpart - the outgoing mail) also set up on your iPhone, when you reply, just tap on the line that starts with CC: Bcc: From. Then go down to the line that has the From address and tap on it. A wheel will pop up with your send from options. Just choose your pop3 account there.
But if I have he pop3 setup on my iPhone I will get a notification there as well as the gmail account correct?
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- Sent from my iPad
Don't know why you've gone to all this trouble of forwarding email, from a quick scan of the 1and1 website, they support imap as well as pop, so just set the account up as imap instead of pop.