One of the biggest criticism of the original iPhone and the iPhone 3G was its inability to send or receive MMS messages - or text messages that contained additional media such as images, audio or video.

The iPhone 3.0 OS update changes that - although it does require the support of the mobile operator and O2 in the UK offers full MMS functionality.

But to send or receive MMS messages you have to first enable the functionality:

1. Click on Settings
2. Click on Messaging
3. Now switch on MMS Messaging
4. To send a MMS message you simply click on the Messaging app icon and click on New Message. You will note there is now a camera icon to the left of the text input area. Click on this and you will be prompted whether you want to take a new photo (or video if you have an iPhone 3GS) or use one that is in the Library
5. Make your selection and a thumbnail of the will appear in the input box (note that MMS images will normally be compressed heavily from the original in order to save bandwidth - typically the maximum size of image or video is just 300k)
6. Click on Send

Note: MMS messaging can also be used to share contact information (as a .vcf file from the Contacts app) and audio files (from within the Voice Memo app).