Don't know about the 3G but the 4s can be connected to an external monitor with a cable that takes the 30 pin to either a VGA of HDMI depending on the connection of your monitor. I have done it with my 4, 4s and 5, they all work great.
Don't know about the 3G but the 4s can be connected to an external monitor with a cable that takes the 30 pin to either a VGA of HDMI depending on the connection of your monitor. I have done it with my 4, 4s and 5, they all work great.