The scrollbar does not show up because the iPhone uses a special thin and translucent scrollbar that is not visible unless you are actively scrolling. To scroll the odds you must use two fingers. The first time you use the WagerWidget you get an notice about but you may have missed it.

We are looking into expanding the odds view so that there is not a blank area were a scrollbar would typically be, so look for that in the future.

Also, thanks for checking out and commenting on the WagerWidget!