Sometimes with apps my Windows 8 phones says “This app needs permission to use the camera?” What does it mean and can you change it in the app’s settings?
Whenever an app asks for permission to camera access,it might be due to -
a) Permission to use camera's flash,
b) Permission to use camera to click photos,
c) Permission to scan codes via camera.
and you know which apps uses these permissions to perform their tasks.
As Matt put it ~ it's a security notification.
Basically it wants your acknowledgement that a feature or function of the app might use your camera at some point.
As far as my experience with Windows phone goes it seems like the "camera permission" is tied in with some other permissions. So on occasion you might see an app request access to your camera although no part of it appears to have any use for it.
As Matt says, it's a security thing. Apps may need access to various parts of your phone (internet access, contact list, location, camera), but this is not always obvious from the description of the app itself (for example, you probably wouldn't expect a "Flappy birds" type of game to use your camera), so Windows Phone gives you this extra warning. It is up to you to decide whether to grant such access or not. The general rule is to grant access if only if you can see why that component or service is needed. If the request seems totally bizarre (as in the dummy example above), the app is probably malicious and should be removed outright.
It's a security check. The app needs permission, because otherwise any app could use your smartphone's camera at any time, which is a bit of a privacy issue.