With a database of approximately 1 million landmarks worldwide, users can enjoy various functions, such as Landmark Navigator which displays the distance to a nearby landmark in the direction the camera is faced towards, and Photo Navigation which displays the distance from the photographer's present location to the place where a tagged photo was taken.

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In fact, she saw it because she was friends with a person tagged in the photo, one of the Zuckerberg sisters.

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Or on a travel site a photo of a temple in Japan could have an app that explains it, and if the photo is geo-tagged, shows a map of the area, and other related information.

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Another friend found that a photo she thought was completely private was visible to me - a relative had tagged her in it, over-riding her personal preferences.

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Tagged images are collected in a new section in your profile and won't show up in your main photo feed.

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