淨係得果電話號碼，有冇方法知道佢係用邊個電訊網絡？幫幫手！

try to call every phone service hotline, the IVR system asks you whether you are existing client or new client; press the phone number into the system and see whether it ask for the password or saying that number is incorrect; it works for 3G Hong Kong phone hotline 3162333 but I am not sure it works for the other companies... check it out

如果只係有個電話號碼
係唔會知道佢係用緊乜野台架
因為而家有 "帶號轉台"
任何手機號碼都可以隨意轉台