How to Turn iPhone 3G Off and On
3G might allow for faster data download speeds, but it also quickly drains the life out of your iPhone's battery. It's a good idea to disable your iPhone's 3G network when are not using it. Plus, under certain circumstances, you must turn off your iPhone's 3G capability anyway, such as when you are on an airplane or in the hospital.
Access the iPhone settings by clicking the "Settings" app icon.
Click the "General" settings option.
Click the "Network" option.
Turn off the "Enable 3G" option by flipping the switch to "Off."
Tips & Warnings
- For maximum iPhone battery life, keep 3G off unless you need high speed data. In that case, turn it on for as long as you need it and then switch it back off.