Your streak counts consecutive days on which you've completed at least one lesson.
Completing enough of a lesson to hit your daily XP goal on a given calendar day (in your local timezone) keeps the streak alive for that day. The streak counter and daily goal are connected — see Daily Goals.
Missing a full day without securing that day's goal resets your streak to zero. There's no partial-credit system — the streak either continues or resets.
A streak shield, available from the shop, protects your streak for a set number of days even if you miss completing a lesson — a way to preserve a long streak through a genuinely busy day. Shield duration is tracked and consumed day by day once active.
Reaching 3, 7, 14, 30, 60, or 100 consecutive days each unlocks a corresponding achievement.
Streaks work the same way in Guest Mode and with an account — the difference is that an account backs up your streak via Cloud Sync, so it isn't lost if you lose access to your device.
Hitting your daily XP goal at least once per calendar day, in your local timezone.
Your streak resets to zero — there's no partial credit for a missed day, unless a streak shield is active.
It protects your streak for a set number of days even if you miss completing a lesson, consumed day by day while active.
The streak itself works the same way, but it's stored only on your device — creating an account backs it up via Cloud Sync so it survives a lost or reset device.