The default setting allows you to install apps from the Mac App Store and apps from developers that have a unique Developer ID from Apple.

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By default, Mountain Lion will only let you install programs carrying these certificates.

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That means that the YouTube app, the previous version of which was created by Apple, no longer will be a default app on the devices, so people will have to manually install it.

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Worse, Linksys' devices come with a default password, "HomePlug, " rather than forcing you to install one of your own.

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When users install Google Maps on their iPhone, the option to share location data with Google is switched on by default.

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