If you have already unlocked Pillow's premium features and then deleted or installed the app on another iOS device, you can restore that purchase for free as long as you have set up your device with the same Apple ID that you used to purchase Pillow in the first place.
To restore your Pillow Premium purchase, please follow these steps:
Ensure that you are logged in with the same iCloud/Apple ID that you used to purchase Pillow Premium in the past (all purchases are tied to their Apple IDs).
Open Pillow on your iPhone or iPad.
Tap on the "Settings" icon in the top right corner.
Select "Restore purchase".
If you are experiencing any problems with that process, please contact our support team.