Hi @samk,
Kindly please be informed that KoBoToolbox at the moment only offers KoBoCollect andorid app for collecting data that can be downloaded from the google play store. It does not provide you an IOS version of the same. However, you could still collect data through an IOS device via Enketo aka web forms. To learn more on the same please feel free to have a look at our support article WHAT ARE ENKETO WEBFORMS? and COLLECTING DATA THROUGH WEB FORMS.
Or this workaround discussed in our other post should also help you install the Collect android app to OS other than the Android OS:
Have a great day!
