English summary (data retention & deletion):
manpoke retains user data (step count, nickname, member color, group membership, and login
credentials) only for as long as the user's account exists. Step counts are stored as the latest
value only and are overwritten on each update; no step history is accumulated. Users can delete
their account and all associated data at any time from within the app
(menu ⋮ → "アカウントを削除" → confirm); the data listed above is deleted immediately.
Users who cannot access the app may email kaosanhirosan@hotmail.co.jp with their nickname, and the
account will be deleted within 7 days. No user data is retained after account deletion, and no data
is required to be retained by law. Copies remaining in the cloud infrastructure (Firebase) are
erased within 30 days. Deleted data cannot be restored.