As someone in the aviation business and working very closely to security systems I would say that if you try to pass through security points with a modified cell phone to carry intresting stuff, you will have some unpleasant time. All the security staff or the police do not like any kind of a container that is modified from a tool etc. The most important part is not hiding anything from them, you directly become a suspect.

The airport that I work for was the first airport from the region that was authorized by FAA to start direct flights to US after 9/11.

Burak