Apple is reportedly working on making the iPhone completely unhackable but in the meantime you can take some steps to make your iPhone less vulnerable to hacking with just two simple steps. Increasing the length of your passcode to 12 digits will make it virtually impossible to unlock your device with brute force techniques, as it would take hackers an estimated 1,268 years to crack an iPhone that’s protected with that long of a code.
Of course, having to enter in a 12-digit passcode when you first boot up your iPhone is incredibly annoying. This is likely why most users are happy to stick with the standard six-digit passcode that takes an estimated 11 hours to crack via brute force.
For an added security measure, 9to5Mac also recommends disabling your phone’s iCloud backup and instead using encrypted backups in iTunes to protect your data. You should also make sure to delete your existing iCloud backup to ensure that none of your old data is still accessible on the service.