So seeing you have made a separate post, I think you might be confused. You don't need an Asmodee account to link between Steam and IOS. After you've bought the game on steam please follow these steps to link the two devices:
1. On your Phone, go to the main menu > Options > Settings > Link
2. Click the "Link" button next to Desktop
3. Take note of your PFID and the temporary secret key
4. On your PC, go to main menu > Options > Settings > Link > Enter Link Code
5. Enter the PFID and secret key you previously recorded on step 4
6. Press "OK"
Our Asmodee system is still in it's infancy, so we're still trying to work out all the kinks. Hope this helps