By "we", you mean https://zerofasting.com/ ? Seems like a nice app!

I tried that app a very long time ago, and then in an update they forced users to create an online account with no local use option. I promptly removed it since I’m averse to creating online accounts when I see no good reason to do it.

I use it without an account.

Edit: Tried it again on iOS and there’s no way to proceed after the initial questions without creating an account. Deleted it again.

You can log in with Apple ID, never share your email and remove the app from your account whenever you please. If that's too intrusive for you, I'm surprised that you've managed to sign up to HN so you can write a comment.

I didn’t sign up to HN just to write this comment. Also, HN doesn’t require providing an email address to create an account, unlike this app. I like my local-only preferences.

Sorry, my mistake. Turned out I was signed in via Apple ID.

That is us!