I don't think there is a way to see the F3BarGauge in IB, but you can add a UIView as a subview of your main view in IB, size and position it as you like, and then in code, add the F3BarGauge to the subview.
After Edit: Actually, after looking at the author's demo project, you can see it in IB. Just copy and paste his view from the demo project into a view controller (after deleting the default view first).