As AT&T promised, iPhone 3G and 3G S users today gained the ability to send Multimedia Messaging Service (MMS) messages.
To enable MMS, users must first have iPhone OS 3.1 installed, and then the AT&T carrier update v5.5 which is installed through iTunes. Once the update is in place, phones must be rebooted, and then the Messages app will feature a camera icon in the lower left corner, which triggers multimedia messages to be sent.
For users of the original iPhone, MMS cannot be natively sent or received. However, AT&T has a service which sends users a standard text message with a link to Viewmymessage.com, where messages can be viewed for up to 7 days on non-MMS compatible, but Web-enabled, phones.
Apple also warns that the Messages application does not support sending or receiving MMS content over Wi-Fi connections, so if you’re on a slower EDGE or GPRS connection, you’ll just have to wait for your MMS to be sent. Of course, Apple says you can still send pictures through Mail over Wi-Fi as a workaround to slower connections or poor coverage.