RulerPhone turns your iPhone and its camera into a measuring tape -- all you need is an item that you probably carry around with you already: a gift card, MetroCard, driver's license, or anything with the exact dimensions of a credit card. You can download RulerPhone for $2.99 in the App Store if you want to measure distances of up to 12 feet or you can pick up RulerPhone Lite for free if you don’t need distances longer than 1.5 feet.

Download: App Store Apps | iTunes Link

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