Do I need to any code to my theme for Postie to work?
No.
Post by Email with WordPress
Post by Email with WordPress
FAQ Category Installation
I read somewhere to add an iframe to my footer. Should I do this?
No. Do not add an iframe in your footer to get Postie to check mail periodically. Postie uses WordPress cron to automatically check mail. To force a email check periodically, set-up a cron job. See our cron troubleshooting page.
Is the IMAP extension required for Postie?
The IMAP extension was required for some functionality in Postie versions before 1.8, but is no longer needed.