At the top of the timeline tap on the marker icon to add a marker.
You can add the following markers in the timeline:
Tap on this icon to place a Mark IN and a Mark OUT at the extremities of all existing drawing sheets and clips, or at the extremities of the selected sheets/clips.
IN Places a Mark IN at the current frame.
OUT Places a Mark OUT at the current frame.
Places a marker at the current frame.
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Mark IN and OUT set the limit of the portion of frames that can be played and exported.
Long-touch a marker and drag it to move it to another frame in the timeline.
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Double-tap on an existing marker to rename it, change its color, or delete it.
You can choose to have the markers names displayed at all times: in the settings, go to Timeline and enable the option Show markers description.
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To flip between markers, in the Flip tab of the settings, choose Markers as the flip style.