In this Canvas release (March 20), students can use their webcam to submit File Upload assignments.
In SpeedGrader, instructors can reassign an assignment to an individual student and ask them to redo their submission. In Course Settings, the Participation menu includes an option to select course dates by term or course. Files linked in the Rich Content Editor can be previewed in an overlay or inline.
This is an abridged version of the full release notes and references. The full article can be found in the Canvas Community site.
Below is a screen cast summary of the release notes.