I bought premium on macbook but restore purchase function doesn’t work on iphone only advice/support you will is apple troubleshoot page and they will ask you to refund
So don’t buy it if you are plan to use more than one device plus you can resize anything calendar will be very small on macbook.
Sync between iOS devices
It would be great if you could add the function to sync the list between iphone and ipad. Or backup using iCloud. Indeed, I like this app so much. Keep it up!!!