iOS Charting Documentation - SciChart
SCIPinchZoomModifier

SciChart features multi-touch zooming via the SCIPinchZoomModifier. To enable pinch zooming, simply add a SCIPinchZoomModifier to your SciChartSurface.ChartModifier.

Objective C:

SCIPinchZoomModifier * pzm = [[SCIPinchZoomModifier alloc] init];
[pzm setModifierName:@"PinchZoom Modifier"];
[surface.chartModifiers add: pzm];

Swift:

let pinchZoomModifier = SCIPinchZoomModifier()
pinchZoomModifier.modifierName = PinchZoomModifierName
chartSurface.chartModifiers.add(pinchZoomModifier)

See Also

ChartModifier API