1) Are you referring to using a 3G router on the IP camera network, or using a 3G router outside e.g. from the office? In either case, both are fine. For me, the issue seems to be more from a network to network hop. My home network is on Singnet. If I use M1 3G network (using my iPad2), the pictures are slow (low fps). However, using a SingTel network (using my Galaxy Tab 10.1, or my mobile phone), the better IP cameras can give me continuous motion (higher fps).
2) If you camera has pan-tilt (PT) function, most apps allow you to pan left-right tilt up-down.