In science there is no such thing as electro-sensitive people so the question is redundant. Cell phone signals aren't all that different from any other kind of radio signal although they are very high frequency. They aren't all that strong a signal in the first place which is the principle behind the cell.
A cell is a local area and when you move around you are connected to the nearest cell and automatically switched to the next cell as your signal gets stronger for that cell. That's why so many people can use cell phones at the same time. otherwise it wouldn't be possible.