Contact
Lettra is made by a very small team, and every message is read. Pick the address that fits and you will reach a person, not a form.
Something is not working
Email support@lettra.app. If a word you are sure about keeps being turned down, include the date and the word: answer lists are hand-built, and genuine misses get added. For a problem in the game, say which browser or device you are on and what you expected to happen.
Feedback and category ideas
Email feedback@lettra.app. Ideas for categories are especially welcome. A category works when it is general knowledge rather than a specialism, when most of the 26 letters have at least one answer a reasonable person could reach, and when the answers are satisfying to find rather than a list anyone could recite. “Things in a kitchen” works; “Nobel laureates in chemistry” does not. If you send one, a few example answers for the awkward letters (J, Q, X, Z) help it get made.
Reporting a wrong verdict
Lettra decides whether a word fits the category, and like any judge it is sometimes wrong in both directions: a fair answer turned down, or a stretch let through. Either kind is worth a message to support@lettra.app with the puzzle date and the word. Verdicts are reviewed, and corrections go into the answer lists so the next person to try that word gets the right answer at once.
Privacy
Questions about your data go to privacy@lettra.app. The short version is in the privacy policy: there are no accounts, and your play history lives in your own browser.
Before you write
The FAQ answers the common questions, and the rules page explains scoring and why a word might be rejected.