Winter Arc Tracker: Winterlock

Winter Arc tracker and 90-day challenge app: write your daily rules, sign your contract, check in every day.

The Winter Arc is simple: while everyone else coasts through the cold months, you lock in. Pick your window (Oct 1 to Dec 31 is the classic), write the daily rules you refuse to skip, sign your name, and show up every single day.

WRITE YOUR NON-NEGOTIABLES
Up to 10 daily rules: train every day, 10k steps, no alcohol, read 10 pages, up before 6, no phone after 9pm. Yours, in your words. Tap a suggestion or type your own.

SIGN THE CONTRACT
A contract card with your rules, your dates and your signature. Post it before day one. Telling people is half the discipline.

CHECK IN. LOCK THE DAY.
Every day, check off each rule. All of them done = a perfect day and a streak. Miss one and the grid shows it. No hiding.

WATCH THE ARC FILL UP
A 92-day grid (or however long you set), perfect-day streak, best streak, rules hit rate, days left. Share the progress card whenever you want.

BUILT FOR THE LONG HAUL
- Optional daily reminder at the hour you choose
- Works fully offline. No account, no sign-up, nothing leaves your phone
- Any dates: Oct 1 to Dec 31, 90 days from today, Nov 1 to Jan 31, or your own
- Available in English, German, Spanish, Portuguese, French and Italian

Free to use, supported by a small ad on the progress screen. Your check-in list stays ad-free, always.

Winterlock is a habit tracker, not a coach or a medical tool. The only thing it measures is whether you kept your word.

Recent changes:
Winterlock is now a year-round challenge tracker: Winter Arc, New Year Reset, 75-Day Challenge, Lent, Dry January or your own program. Grace days (one free pass a week), a streak saver for yesterday, a weekly recap card, smarter reminders that skip days you've already locked in. Winterlock Pro (optional): several programs at once, unlimited sealed photos, CSV export, no ads. Your current arc carries over untouched.