On iOS, Ti.UI.TabbedBar currently uses Apple's segmented control widget. Since the name "TabbedBar" implies it uses tabs, it should be changed to use Apple's Tab Bar widget instead (aka: UITabBar). This will also make it consistent with the Android implementation which uses Google's native tab widgets.
Titanium 10.0.0 will be introducing a new Ti.UI.OptionBar (see:
TIMOB-28317) which will use a segmented control on iOS and a material toggle button group on Android. If you want to continue to use the segmented control, then switch to the new OptionBar view.
The attached TabbedBarTest.js can be used to test this change with text-only, image-only, and image/text tabs, which will look like the below screenshot. Note that Apple's UITabBar expect both an image and title to be assigned to all tabs.