iPhone 3GS has no front camera. Those are sensors, an ambient light sensor to detect the light in a room and adjust screen brightness, and another sensor to detect your face during a call to turn off the screen so you don't press buttons on a call.
by going on camera and then go on the optins and then operate it. hoped it helped!
if you want to record videos, then you can find tons of apps that will allow you to shoot videos.
yes
Yes. If you look up "camera zoom" on the App Store, you will find several applications that you can use to zoom in on the camera. I have also posted links to some apps.
Use a hammer
yes
The screen size remains the same, the quality of the display however couldn't be more different.Apple has developed something they call the Retina Display for the iPhone 4. Basically they took the old display and made the pixels far smaller. This enabled them to fit four times the pixels on the display which makes the picture quality far superior to the older 3GS.In other words the iPhone 4 has same sized screen as its predecessor but its display boasts 4 times the picture quality.iPhone 3G and iPhone 3GS screen are not same in size. handypart.com
The apple iphone 3gs it rocks!!!!!!!!!!!!!!
It uses iOS
use the newest version on green poision
No
Yes, iPhones use a normal sim card.
No