How to send photo to another mobile phone using iPhone?
How to send photo to another mobile phone that accepts a photo?
Most cell phones can do this. Why not iPhone?
iPhone only allows photo sending by e-mail.
There is one workaround. Send the photo to a phone's cell email address. To get someone's phone's email have them send you a message from their phone to your email that you use on your iPhone. The email should be their 10-digit number@carrier.com (or .net) Example 5551234567@vtext.com.
You have to send an email like Eagle suggests. Different carriers have different setting. Check http://www.notepage.net/smtp.htm for an insane list of carriers and their settings.