I've entirely rebuilt the Android version of R Instructor... Entirely new interface, major stability enhancements, and major under-the-hood optimizations. Enjoy! 

Oh, in addition to making the core code of the Android app that much better -- I've added additional content, which is listed below. Don't worry iOS users, an updated version of the app is currently being reviewed by Apple.

Additions to base plots section:

Add a grid to a plot

Add and modify arrows

- change arrow head shape

- change arrow head length

- change arrow color

- change arrow line width

- change arrow line type

- change arrow head angle

New plot section (requires ggplot2):

How to make qplots:

- Boxplot

- Histogram

- Density histogram

- Frequency polygon

- Line chart

- Path plot

- Scatter plot

- Conditional smoother

Modifications to above qplots):

- add color, either specific colour or according to a third variable

- add title or change title font size

- add facets

- adjust line widths and point sizes

— there will be a lot more material on ggplot2 coming in the next update —