Sophos have published a list of key things to do with your smartphone to keep it secure :-
http://nakedsecurity.sophos.com/2013/10/08/10-tips-for-securing-your-smartphone/
And now is a good time to review that list.
Most of us spend more and more time with our smartphones, and in turn they become more and more embedded into our lives with more and more personal information. Paying attention to security is admittedly tedious sometimes (at least the preventative kind), but it saves a great deal of anguish in the event of a smartphone being stolen.