Sketching is one of the best companions to note taking. Or one of its best forms. Currently Agenda has limited sketching capabilities similar to (or possibly based on) Apple Notes.
What I’m personally missing is an infinite canvas, pinch to zoom in and out, and rotate a selection. These three additions would complement my workflow so that in between of writing notes I could directly sketch out my thoughts, say wireframes of multiple screens of an app on a single canvas.