I can’t download SmartRace for free on macOS, although I already own the iOS version of Smartrace

It may seem like you would need to pay again for SmartRace on the macOS app store, even if you already own SmartRace for iOS (in which case the macOS version is included) and even if you’re logged into the app store with the same AppleID you used to buy SmartRace for iOS. In this case, please just act as if you’d like to purchase SmartRace again for macOS and go through the process. At one point, the app store will recognize that you already own the app and will let you download it without paying again.