Use Touch Zones
When we use certain visualization types, such as scatterplots, we may end up with a lot of data points on a small screen. If we provide hover behavior for those points on the web, it may be tempting to do so on mobile as well. However, If the density of these points is too high, due to the touch area being so large on mobile (relative to a mouse cursor,) we may need to alter the way our users interact with those points.
There are several ways in which this can be accomplished:
If your data demonstrates some clustering behaviour, consider defining touch zones that surround the clusters.
If there interesting element about your scatterplot has to do with an increase in the x or y values, consider dividing up the screen into appropriatly-sized touch zones and responding to those, instead of the values themselves.