To increase the security of your iPhone passcode from a simple 4 digit pin to something more complicated please follow these steps.
First, tap settings, then scroll down and tap Passcode:
On the passcode screen turn off the slider for "Simple Passcode", then change your passcode to something more secure:
Going forward, after you type in the passcode to unlock your phone, you'll need to tap OK:
First, tap settings, then scroll down and tap Passcode:
On the passcode screen turn off the slider for "Simple Passcode", then change your passcode to something more secure:
Going forward, after you type in the passcode to unlock your phone, you'll need to tap OK: