Meadow has no accounts. There is no sign-up, no password and no server holding a copy of your meadow. Everything you log stays on your iPhone, and the optional iCloud sync goes through your own Apple Account, not through us.
These articles explain what that means in practice: what stays on the device, the two small anonymous things we do collect and how to switch them off, and how to delete everything if you want to. There is also a short piece on reminders, which are scheduled by the app on your phone and never sent from a server, so there is nothing to track. Your mood is recorded as words, never as a number or a score, and the app works with no signal at all.
The last article answers whether Meadow connects to Apple Health. Not yet, and when it does it will be read-only, permission-first, and limited to the categories it needs. We would rather ship that properly than quickly.