Yes; the Contacts Journal app for Mac requires a separate purchase from the "Unlimited Personal Plan" on iOS (and vice versa).
Once you have both versions, there are 2 ways to sync your data between them. You can use the CloudSync sync option, which syncs your information automatically between the two devices. This is our recommended option. You can also use the DropBox option, which requires you to "Save to Dropbox" after making changes on one device, and then "Fetch from Dropbox" from the 2nd device. This is a little manual, but also works well in some cases.