In the premium version you have access to the whole API, in the standard version you do not.
Have a look in the header files, like SChart.h
Some methods are available to both premium and standard, others are not. If you search for these in the Shinobi header files, it should be quite clear.
/** Add an annotation view to be displayed on the chart plot area
@param newAnnotation The new annotation to add to the chart.
- (void)addAnnotation:(SChartAnnotation *)newAnnotation;