Originally Posted by
seamores
..the reason you can talk on your cell phones once the plane has landed is because they use different instruments for this phase of flight than for taxiing before takeoff. Cell phones may disrupt the instruments needed for taxiing before takeoff.
You sure about this? Isn't it much more that they run the checks on the flight guidance and navigation while taxiing for take off while after landing the state of these instruments is irrelevant?