Reporting a sighting. Open any sighting posted by another spotter and tap the ••• button. Choose Report Sighting, pick a reason, and add a note if it helps. Reports are reviewed and violating posts removed, usually within 24 hours.
If something needs attention faster than that, email the address above.
Blocking a spotter. Same ••• menu — choose Block Spotter. Their sightings and lists disappear from your feed, map, stats, and lists straight away. They aren't told.
To undo it, open the profile menu at the top left of the feed, choose Privacy, and unblock them under Blocked.
Hiding your name. By default your posts are signed with a handle taken from the part of your email address before the @. To turn that off, go to the profile menu → Privacy → Hide my user name. There's also an option there to rewrite the handle on everything you've already posted.
Deleting your account. Profile menu at the top left of the feed → Delete Account. It takes effect immediately and can't be undone. Your photos, captions, handle, and lists are removed with it.
Privacy. See the privacy policy for what the app collects and what happens to it.