Birthdays can be entered with or without the birth year.
Contacts with birthdays can be imported into the list and then processed independently.
There are no ads and no in app purchases.
All data are local and thus protected.
The birthday list is managed independently of the possibly synchronized contact list.
There is no synchronization with any service or social media account.
No internet connection required.
The birthday list entered can be synchronized to other devices in the same network.