If you have an iPhone you probably have sensitive information on it. If you're a lawyer or businessman, and you use your phone for business, then you almost certainly do. You should enable the Passcode Lock on your phone that requires a 4 digit PIN to access the phone's data. Of course, if you work in a large firm your IT person will no doubt have the ability to do a remote wipe if you lose your phone.
But what do you do if you aren't in a large firm? Or what if you don't like having to enter the passcode every time you fire up your phone? Here is my tip for people in this category. Set the passcode lock to trigger only if the phone hasn't been used for 1 hour (or, if you're really annoyed by the passcode lock, then choose the 4 hour option). True, if the phone is stolen the thief (or finder) will have immediate access to your data. But if the thief or finder assumes that you've not enabled the passcode lock they'll be surprised when it kicks in after a period of non-use.
In other words, if the passcode lock annoys you then at least choose one of the minimal options. It won't annoy you and at least you'll have enabled some security. To set the code go to SETTTINGS > GENERAL > PASSCODE LOCK > REQUIRE PASSCODE.
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