"In" versus "On" was Visual Guide to Widgets

[Gerry Gavigan]

As a native British English speaker you can rest assured that I have no idea 
about grammar but here's my take on the debate by way of example

The dialogue box "In" Kwhatever application had a button "On" it to change 
<something>

(of course, in computing everything is a visual illusion) As has been 
discussed "In" is a 3D word - inside, and suggests something is not 
immediately accessible.  "On" is a 2D word - on top of and is available the 
moment one sees the thing it is on top of.

"The clock is on the shelf and the clock is on the car dashboard - the former 
is moveable the later is not but they are both "On"

FWIW