There are a few touch regions on each table row in an outline in
  MobileOrg.  If you tap the blue icon at the right of each row, you
  will view the details for that node (IMG_0019.PNG).  This is useful
  for editing a node's contents, todo state, etc.

  If you want to dig into the outline, just tap more to the left, on the
  text of the node (in this case, "main.org").  That should present you
  with the child nodes of the file, and you can continue digging down
  from there.

FWIW, this confused me too.  Perhaps a thin vertical line to separate
the active touch regions as a clue that there are two?