What is a habit duel?

1. Pick a positive habit from the library - movement, nutrition, discipline, home or learning. Every habit is one that can be proven in under a minute.
2. Invite an opponent and choose the referee: a third friend, or the built-in AI judge.
3. Set the length: 3, 7, 14 or 30 days.
4. Each day both of you submit proof - a single photo, a video of up to 60 seconds, or a start and end capture for habits that span longer than a minute.
5. The referee sees both proofs side by side and rules a winner, a tie, or a no-show.
6. The scoreboard updates. Winning a day earns points, and winning the whole duel earns a bonus that grows with the length.

A duel is only as honest as its referee, so Forge never leaves the call to the competitors themselves. You choose at creation:

A friend as judge. A third person rules each day once both proofs are in. If an invited friend declines, the challenger invites someone else before the duel starts. A friend judge has a deadline - any day they have not ruled by noon the next day is ruled by the AI instead, so a silent judge cannot freeze the duel.

The AI judge. An AI referee (Amazon Nova) scores both proofs and rules the day automatically. It costs nothing, needs no third person, and rules a tie and flags the day when it is not confident enough to separate the two proofs.

Score, not money. There is no pot, no wager and no cash prize. Day wins and duel wins earn points; the points you earn in a calendar month rank you on a Top 100 board that resets on the 1st, and it ranks winners only, so there is no public losing. Lifetime points never reset - they carry you up 10 levels, from Ember to Mythic, with badges along the way. Referees have a board of their own, ranked on rulings delivered and duels refereed on time.

Starting a duel is free at every length. There is no entry fee. The free plan runs one duel you started at a time, while duels you are invited to are unlimited and always free, and daily proof, judging and both leaderboards are included. Premium ($6.99/month or $39.99/year, 7-day free trial, no card) raises the limit to five duels you started at once. Premium never affects points, rulings or leaderboard position.

More detail on both in the FAQ, and a side-by-side with other kinds of habit app on the comparison page.