SAN FRANCISCO (Reuters) – Twitter on Monday introduced the ability to add color filters to user-uploaded photos, a step that sharpened its budding rivalry with Facebook Inc. Twitter’s filters mimic the popular feature that has defined Instagram, the booming photo service acquired by Facebook this year for $715 million. Although the new filters represent a modest product announcement affecting a small slice of Twitter’s overall user experience, the move carries symbolic weight in the escalating battle between Facebook and Twitter for dominance in the social media sector. …

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Twitter launches photo color filters to battle Instagram, Facebook