Like the Health app on iOS 8 where null/empty data points are not displayed while X axis labels are still there. Using iOS-Charts as the chart library for my project is it possible to achieve the same?
You shouldn't pass a nil, it does not a accept a nil and Xcode will warn about it. What you should do, is just not pass it at all.
You do not have to pass a y value for every x index. You just have to make sure that the y values are ordered according to the x indices.