Amazon.com has bought visual product search company SnapTell Info, of Palo Alto, California, for an undisclosed amount. SnapTell is responsible for the popular iPhone app that allows users to take a picture of the cover of a book, DVD or other product that they want to buy, and connect to an online store in order to buy it, the Wall Street Journal said. Amazon already offers a product search app for the iPhone and other devices, but it relies on humans to match photos and products, while SnapTell’s software automates the process.