Personalize vibrations on your 
iPhone, to know when someone calling, by just feeling it! 

To do it...
>> Open the 
contact for whom you want to assign a custom vibration. 
>> Tap 
Edit -> 
Vibration -> and 
select the vibration you'd like to include, from available list
Or 
create an new vibration.
>>> To do so, select 
Create New Vibration and 
tap on the screen to record a rhythm (
will be translated into a vibration)>>> Approve and hit 
save.
Now you will know who is calling without even looking at your phone even when silent (vibration On)!
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