If an app like Instagram just doesn't do it for you and you want a more authentic photo editing experience, the Holga iPhone 4/4S Lens Filter and Case Kit SLFT-IP4 snaps onto your iPhone then gives you access to 9 different special effects and filters. The filters operate like an old-school rotary telephone, so you can "dial in" your desired special effect. Some effects include Dual Image Lens, which produces two identical images, and Red Filter With Clear Heart Shape Center, which reduces blue and green lights and applies a heart. Available in Black, White, Silver, Red and Blue.
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