I have now confirmed with Smartone-Vodafone that the Internet Browsing plan; now known as IOM plan, indeed only cover HTTP and the corresponding HTTPS traffic. So any web traffic through Mobile Safari on your iPhone and any applications; whether it is downloaded from the Apple AppStore or unauthorized 3rd party, that uses the HTTP Posts and Gets will be covered in the Internet Browsing plan.
Any POP3 traffic will be outside of the Internet Browsing plan allowance and Smartone-Vodafone has a separate POP3 Email monthly plan for HKD30/month. As a result any IMAP or Exchange Push traffic will be count as regular Data traffic. I think this omission of IMAP and Exchange traffic from the Email monthly plan is the wrong thing to do for Smartone-Vodafone. Why would anyone choose POP3 over IMAP or Exchange email is beyond me. Especially when the iPhone is only one of many devices most users will use to access their emails, and definitely not the primary device. I urge Smartone-Vodafone to listen to its customers and change their Email monthly plan.
Please see my original article, “iPhone Hacked in Hong Kong on Smartone-Vodafone” for details of my post and the feedbacks from various readers.