Try it: wheel or pinch on the line to zoom, drag to pan, 0 resets. Press M or the ruler button on the rail, then drag between two points to measure (Δ, % change, slope); the rail's other tools draw on the chart and the drawing stays on its data when you zoom. The wheel works on every chart: the bar zooms by category (and pans by drag), the scatter zooms both axes. The grid and the four tiles show exactly the rows in view.