Hi everyone,
  I am new to autocad and know the basics im using autocad lt. I have downloaded Autocad WS on laptop and on iphone, im having problems with the unit settings i.e when drawing in normal cad i draw a line of 3000 (mm) in a scale of 1:50 when i download to autocad WS and use the Dimension tool it come up with 60.000 as the measurement. Please help.

The cardinal rule of AutoCAD is that everything you draw in model space should be drawn to FULL size no matter what the object is.  You could be drawing a paperclip one day and an ocean liner the next it doesn't matter to AutoCAD.  Scale should only come into play when you switch to your paper space layout and create a viewport.  It is the viewport that gets a scale assigned to it.

Ok thanks that is proberly where im going wrong, i'll give it a go .

Do you know how to work with viewports in paper space or are you still learning?