Contact
Doubled is made and run by one person. Use the feedback form to send a message directly from the game.
Puzzle corrections and account problems get looked at first. If you would like a reply, include a contact email in your message.
What to include
A puzzle looks wrong
Send the puzzle's date. If the answer you had in mind fits the picture as well as the published one does, say what it was — near-misses are how the wording of a puzzle gets fixed for the next time it comes round.
Something is broken
Say what you were doing, what happened instead, and which platform you were on: browser or iOS. The version number in the footer of the home screen names the exact build you were running, and quoting it saves a round of questions.
Your account or your data
Send your request while signed in to the account concerned. You can ask what is stored about you, ask for it to be corrected, or ask for the account and its play history to be deleted outright. Deletion is permanent and takes the streaks with it. See the privacy policy for what is held and why.
Groups
Group admins can rename, remove members, and hand over admin from inside the app. Get in touch if a group has been left without an active admin, or if someone needs removing and there is no one able to do it.
Premium
Purchases are handled by the App Store, so refunds go through Apple rather than through Doubled — Apple holds the payment and is the only party that can return it. If a purchase completed but premium did not unlock, send the purchase details through the feedback form so it can be looked into.
Press, partnerships, and advertising
Use the same feedback form and describe your proposal.
What the feedback form is not for
Hints. Part of the point of a daily puzzle is being stuck on it for a while. The how to play page explains the structure and works through examples, which is the closest thing to a hint on offer.