I think I stumbled on a way to select all data on a sheet by tapping the top left corner, but forget how it works
Thanks, rpear.
That does work on Android. It must have been what I did in the first place. However I noticed it works slightly differently between edit and read only modes. When in edit mode, it selects and highlights the whole sheet, not just the data. In read only mode, it seems to do nothing, but when you go into edit mode all the row numbers and column headings are highlighted, but nothing is selected.
