Another datapoint: There's no cell coverage in my basement. Sometimes you'd get 1 bar, but it will drop soon afterwards. After putting the phone inside a glas

Another datapoint: There's no cell coverage in my basement. Sometimes you'd get 1 bar, but it will drop soon afterwards. After putting the phone inside a glass, I have 3 bars. I took it out, held it by the charm (is that how it is called? The little string with a little figure that you can put on most phones today) and coverage dropped to 0. Works for me.