A month ago Apple issued iOS 6.1.2 in order to patch an Exchange bug. Yesterday, it has released iOS 6.1.3 with lock screen bug fix, Maps updates for Japan and security patches. This update will be available to all iOS devices over the air.
This software update fixes a bug which allowed a complex combination of actions to get around a locked screen. This iOS 6.1.3 also updates Apple Maps for Japan. Users will find more detailed and accurate maps for that region.
iPhone and iPad can easily get the upgrade following the steps of the Settings > Software Update section on the device or by plugging it into iTunes. This update also fixes some holes used to jailbreak devices. If you don’t want to lose that then you shouldn’t update to iOS 6.1.3 now. Apple has not posted the update security content on its site, so you might wait for some time more.