Like a few other Nintendo 3DS games, Monster Hunter 3G supports the Circle Pad add-on peripheral, but it doesn’t require it. If you decide not to use it, camera control — and a bunch of other features — can be used via the touch screen. The video below is Capcom’s Tokyo Game Show presentation of Monster Hunter 3G. It shows off a variety of these features (look around the 23-minute mark):
The camera can be controlled manually with the use of a virtual d-pad on the bottom screen. As reported previously, another panel, the Target Camera, allows you to customize how the camera is re-centred. If Target Camera is toggled on, tapping the L button turns the camera in the direction of the monster. If it’s toggled off, tapping L re-centres the camera behind you. If you want to re-centre it behind yourself with Target Camera on, you can tap L twice.
Another panel on the touchscreen is the Item Pouch. Tapping this brings up a display of the items you’re carrying, so you can access them by tapping them. You can also go through your items using buttons.
The touchscreen can also be customized to an extent. You can either have the map displayed on the top screen or have it displayed on one of the panels on the bottom screen. The same can be done for the Status of your companion hunters. The Target Camera panel is one of the optional panels as well. You can see what else can be done with the touchscreen in the video above.