The new iPhone 5S comes with a fingerprint sensor called Touch ID that lets you unlock the device and make transactions on the iTunes store without a password. The system has been bypassed by Chaos Computer Club- although it isn’t easy and requires quite a lot of planning and gear:
First, the fingerprint of the enroled user is photographed with 2400 dpi resolution. The resulting image is then cleaned up, inverted and laser printed with 1200 dpi onto transparent sheet with a thick toner setting. Finally, pink latex milk or white woodglue is smeared into the pattern created by the toner onto the transparent sheet. After it cures, the thin latex sheet is lifted from the sheet, breathed on to make it a tiny bit moist and then placed onto the sensor to unlock the phone. This process has been used with minor refinements and variations against the vast majority of fingerprint sensors on the market.