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The Lesson is a collection of notes that are scheduled to be studied using a spaced-repetition algorithm. When the Lesson feature is enabled on a Case, the notes in that case are automatically added to the Lesson. You can enable the Lesson feature on any number of Cases at the same time and then use the Lesson as a cumulative review of everything you’ve studied up to that point.
Studying Notes 
Tap the Study button at the bottom center and then choose to study either the Lesson or a specific Case
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