The civilization bottleneck theory explains The Great Silence, why there are no radio or TV signals from other stars. Every natural selection civilization self-destructs itself at a certain stage of political&military competition.
Cellphones are not isotropic radiators.
Here is the general idea of a cell phone radiation pattern: http://www.raymaps.com/wp-cont...
Obviously, it does not have a directional antenna, simply because a smartphone does not know to what tower it is connecting so it radiates in all direction.
Yes, theoretically id does not radiate from one point, but practically speaking it does.
It has just been discovered that research causes cancer in rats.