Only one subscription is needed for Premium on all platforms. If you have purchased Day One Premium (or Plus) and it is not showing up on all your devices, we have some steps that may help.
Ensure your User ID Matches on all devices.
Restore your purchase: please follow these steps on the device where you purchased the Premium subscription (or Plus):
The Restore Purchases button must be done on the device where you originally subscribed. That will send the receipt info to the server and then to the other devices. The icon for iOS and Mac is slightly different. See below:
Day One > Settings > Advanced > Select “Restore Purchase”
Day One > Settings > Account Status > Select “Restore”
Go to Day One > Settings > Support > Restore Purchases
Or on the upgrade screen there is a button for Restore Purchases
The Mac App Store and iOS App Store are handled separately by Apple, so it is possible in some cases to subscribe on both platforms. Only one subscription is needed for each Day One account.
If you notice you have two Day One Premium subscriptions on the App Store or if you were double-charged by Apple for Day One, please cancel one of these as soon as possible. We personally recommend canceling the duplicate subscription and requesting a refund from Apple for the platform you are less likely to upgrade in the future. For example, if you are more likely to get a new iPhone than a new Mac, cancel the subscription on the Mac. They are differentiated by the icon in the App Store.
If you were charged for two Day One Premium subscriptions on Apple, it is possible to request a refund from them for one of these. Please go to https://reportaproblem.apple.com/ to initiate that process.
For future reference, your data will not be deleted if you cancel the subscription. You always keep your data regardless of the subscription status. For more details, please check out this article.