How to Set an Alphanumeric Passcode on your iPhone or iPad<img style="float: left; margin-right: 10px"  src="

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If you are using a passcode that is made of 6 numbers or worse just 4 numbers, then you may want to change based on the report earlier in the week which revealed that a 6-digit passcode can be cracked in 11 hours and the 4-digit passcode in just 6 and half minutes using a new and relatively cheap technology called GrayKey to unlock iPhones.    
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How to Set an Alphanumeric Passcode on your iPhone or iPad