I don't have a smart phone, and I don't know if this applies to the O/P, but I heard something on the radio yesterday about privacy issues & smart phones (like how stores in Malls will pick up your signal and send you an ad).....and the guy was saying that most people don't know that you can (and should) turn OFF the WiFi feature within your phone.
shrug
Well as a
purely educational hacker, I can tell you that WiFi isn't the only thing you should be worrying about. You should also avoid using bluetooth in crowded places.
Regardless if the WiFi hotspot is password protected, private, etc... It only takes one person with a packet sniffer to come along and catch all the data flowing from your device to the wireless access point or router, then crack that data, which will recover all of the information you've been transmitting as well as the password to connect to the hotspot. It's true that a good encryption can be a life saver, especially against amateurs. But truth of it is that any encryption can be cracked, it only takes time.
No one is ever going to be completely safe when it comes to computers, but ignorance is bliss right? ^_^
Now back on topic... I'm not very fond of cell phones, smart phones, or any kind of device I can be annoyed by in my pocket. However I think there is a lot of potential for such devices if you modify them to run off the beaten path. There's a lot of people hard at work to get them running on operating systems such as Linux, which are far more secure, and you can bet your bottom dollar there aren't any key loggers because it's all open source.