blactom Wrote: is there a way to track mobile phones, when turned off or without wifi...probably using only IMEI ?
Yes, you need access to SS7 but all mobile phones can be tracked.
EDIT: If you root the phone you can control all access even when you think its turned off
EDIT2: There are things called IMSI catchers that more closely match your original post but they are only useful for tracking a users location not what ison the phone itself but thought I should mention it since its still working on the newer protocols check the RFC's if you don't believe me
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. - BenjaminFranklin
