If you delete your account, all your data will disappear in the app, including your date of birth, tarot history, notes, etc. If you delete only the app and then re-upload it, your profile will be populated with your previous birth information.
If you didn't delete your account, and logged into the app through your Apple ID, and then logged in also through your Apple ID on another device, your date of birth will be restored, as will your tarot data history, notes, etc. It is important to log into your account using the same login method.
If you download the app to another device and hit the restore button, only premium access will be restored, not your profile history. You will need to log in to the app to restore all your data. Under the same login methods.