Просто добавьте несколько графиков на график с графиком addPlot
CPTScatterPlot * sPlot = [[CPTScatterPlot alloc] init];
dataLineStyle = [CPTMutableLineStyle lineStyle];
sPlot.identifier = @"SomeIdentifier"
dataLineStyle.lineWidth = 1.0f;
dataLineStyle.lineColor = [CPTColor redColor];
sPlot.dataLineStyle = dataLineStyle;
sPlot.dataSource = self;
greenCirclePlotSymbol = [CPTPlotSymbol ellipsePlotSymbol];
greenCirclePlotSymbol.fill = [CPTFill fillWithColor:[CPTColor redColor]];
greenCirclePlotSymbol.size = CGSizeMake(5.0, 5.0);
sPlot.plotSymbol = greenCirclePlotSymbol;
[graph addPlot:sPlot];