KDay celebrates every 1000 days of someone's life. A person's next k-day is their days-alive count rounded up to the next multiple of 1000.
KDay can only count for people whose birthday including birth year is known. Contacts with a birthday but no year appear in a separate section — add the year to their contact card, or tap the paper plane to ask them directly. Contacts without any birthday don't appear; add one in the Contacts app or add the person manually with the + button.
If you granted access to only selected contacts, KDay sees just those. Allow full access in iOS Settings → Apps → KDay → Contacts. You can also import birthday events via Settings → More birthdays → Import from calendar.
Check iOS Settings → Notifications → KDay. You always get a notification on the k-day itself; a heads-up lead time can be chosen in the app's settings.
Everything stays on your phone — see the privacy policy.
Email: kday.support@pvdc.be