SudokuDaily
No. Every game mode is playable offline without signing in. You only need an account if you want leaderboards, friends, and cross-device sync.
Pro is a one-time unlock that removes limits and opens the full set of modes and features. You can restore it on any device signed in to the same Apple ID.
Open Settings inside the app and tap Restore Purchases while signed in to the Apple ID you bought Pro with.
In the app, go to Settings → Account → Delete Account. This permanently removes your profile, scores and friend connections from our servers.
Streaks use your device's local calendar date. Completing the daily puzzle each calendar day keeps the streak alive.
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