Are oval chainrings also available for the TrueBike-base and TrueTrainers?
No, virtual oval chainrings are only available for the TrueBike.
Can I select the virtual oval chainrings via the gear shop in the TrueKinetix app?
No, the virtual oval chainrings can only be selected via the screen of the TrueBike. You do not have to use the TrueKinetix app.