I think she has the freedom to do so.
I wanna ask, would your boss not allow you to
buy a cell phone?
same apply to our maids.
they are not slaves and should be treated as human.
it's quite normal to have a cell phone but the condition is
she can use it after she finishes her work and not affect her work
why not tell her your expectation and discuss with her
even if you forbidden her usage / possession of mobile phone, she can / may still buy one and talk on the phone behind your back so there is no point in "話個比佢知唔可以出電話"
I guess 9.9 out of 10 maids nowadays would have their cell phone. I am not for or against you but that's really the norm.
I'm so interdsted to know if anybody else's maid do not have cell phone, could you post here to tell us cuz I truely admire those maids without cell phone and how I wish I can have such maid too.