That's when you realized what had happened: Your friend had accidentally pressed the redial or speed-dial button on their cellular phone, which then placed a call to you.

那是在你明白过来是怎么回事的时候：你的一位朋友不经意地触碰了他的手机上的重拨或速拨按钮，于是拨通了你的电话。

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Parents can program a third button with up to 20 other speed-dial options, and set the device to only accept calls from those numbers.

FORBES: Mobiles For Minors

The design is simple: it's just a plastic shell with a shutter button, a dial for controlling shutter speed and a hand grip -- the sort you'd normally find on a compact camera.

ENGADGET: Hands-on with Snappgrip, a case that turns your phone into a point-and-shoot