Support.
Write to support@keitgen.de. A person answers — usually Joseph, usually within a day or two.
Mention your device and iOS version. The app keeps no personal data, so we know nothing about you until you write.
Frequently asked
Why only one puzzle per day?
The newspaper never gave you two. One puzzle, taken seriously, is the point — and it is the same puzzle for everyone on Earth, so you can talk about it. If you want more anyway, the unlock removes the limit.
Why are there no hints?
The newspaper could not offer any either. The app stays silent even when you fill in a wrong number; checking your work is part of the puzzle. Pencil marks exist, and you can turn even those off.
What does the unlock include?
Unlimited puzzles, for a single one-time purchase. No subscription. Everything else stays exactly as it is — the absences are the product, and they are not for sale.
How do I restore my purchase?
In the app, open the menu and choose Restore Purchases. Make sure you are signed in with the same Apple Account you used for the unlock. If it does not come back, write to us and we will sort it out.