Fact and Fiction
The regulations (what there are of them) regarding the use of mobile phones is a bit mixed up to say the least.
I.E. It is the CAA etc that object to their use on or near the ground (interfere with ILS Etc) but it is the phone companies themselves that object to there use in the air.
Can you imagine the poor little GSM network trying to hand over 300 mobile phones going from cell to cell at over 500 mph? The network would crash!
As was stated earlier, there are no real regulations and only guidelines which can vary from company to company and country to country. Probably from aircraft to aircraft too when you think of the implications in a fly by wire environment.
Don't know about 1000 feet limit. I would say that I can use my phone more than 1000 feet from a cell so I would say that was a load of *****!