How are my dates predicted?
From the length you gave at setup, until you've logged a couple of full cycles. Then from your last six: the middle length, with a window as wide as your cycles usually vary.
My period dates are wrong
Open Calendar, tap the day and edit it. You can move a start, set an end, add an earlier period or remove one logged by mistake.
What does my partner see?
Your phase and your period window. Never your logs, symptoms or notes.
How do I stop sharing?
Settings → Invite your partner → Stop sharing.
How do I delete everything?
Settings → Technical. Erase clears this phone. Delete account and data also removes your account and backup.
Can I use Seventh as birth control?
No. Likely fertile days are an estimate, not contraception.
Still stuck?
Write to mittxldesigns@gmail.com. We read everything.