You can use MMS and Tethering on the iPhone 3GS. So first go to the settings and there you have to click on general and then go to network. there you can see Cellular data network, VPN, internet tethering etc. Now you have to click on internet tethering and turn it on. When you turn it on, it will give you two option to connect first is Bluetooth and second is USB so you need to click on "USB only". Now go to the message and create a new message and click on the camera icon to choose picture you want to send and then send it to the number you want.