There is technically a way to make your iOS device able to pick up an ANT+ signal, however, it is someone complicated and a bit expensive
Firstly, you need a Wahoo ANT+ Key. This is the only key that is designed to work with third parties, so it is the only one that will successfully work with TrainerRoad.
Now you may notice that the Wahoo Key uses an outdated 30 Pin connector, which means you will also need an adapter to the standard Lightning connection. This is where things get tricky. The issue is that Apple discontinued this adapter, and many of the third party versions lack the internals necessary for constant data transfer. In other words, they are good for syncing and charging, but won’t work with TrainerRoad.
If you have an Apple Certified adapter from back when they originally made the switch, that would be your best option. If not, you can scour the internet for the few that remain, or buy a third party version through a company that will allow free returns.
I’m sorry I don’t have a more elegant solution for you here; sadly we don’t have control over these types of hardware supplier limitations.
If you have another device such as a laptop, that would likely be your best option to get things up and running properly.