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Why are all these apps asking for microphone access?

Which apps?

In iOS 7, apps must request permission to use the microphone, which the user can accept or deny.

Apps like Shazam request microphone access because they use the microphone to hear (Shazam listens to a song and identifies it for you).
 
Shopkick and some other apps. Did they always have access, but iOS 7 changed it to ask for permission?
 
Looks like quite a few have access to the microphone. Glad they changed to ask for permission.
 
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