Login, password, blocking, deleting your account, and privacy.
Go to Profile > Account > Change Password. If you originally signed up with Google and never set a password, you'll see an option to set one there for the first time instead, so you can log in either way afterward.
Yes — signing in with Google will either link to your existing account (if the email matches one that's already verified) or create a new one automatically, so you don't need to remember a separate password at all.
Open their profile, tap the "..." options menu, and choose Block. Blocked accounts can't interact with you, and you can review or unblock anyone from your blocked list in Profile > Account.
Go to Profile > Account > Delete Account. This permanently removes your account and data — it can't be undone, so make sure it's really what you want before confirming.
Only what you choose to share is visible to others — your challenge's own Visibility setting controls that on a per-challenge basis. See the Privacy Policy (linked from the Legal page) for the full details on what's collected and how it's used.
Yes — your account, challenges, and data are the same whether you're using the website or the Android app, since they talk to the same account behind the scenes.

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