Apple’s iPhone 5S and 5C have sold much better than expected since their release Friday. Customers have bought up all of Apple’s initial supply of the 5S, despite concerns about the device’s signature fingerprint scanner, designed to protect users’ privacy. The company has already sold 9 million of the new iPhones:

The sales figures outstrip analysts’ expectations for the opening weekend. Estimates for the phones’ sales ranged from 5 million — the number of iPhone 5 models Apple sold on that model’s opening weekend — to 8 million.

Company stock opened up 5.2 percent to $492 a share.

Apple didn’t specify which iPhone colors were the big favorites with consumers, though more anecdotal reports suggest that the gold iPhone 5s was far more popular than the silver or “space gray” models. The gold version was the first to run out on Apple’s Web site, and several customers reported that they were having trouble finding the phone in stores if they weren’t at the very front of the line.

As for the more colorful, plastic-backed iPhone 5c, at least one firm estimates that nearly half of its customers favored a blue or pink phone. Slice, an online firm that helps users track their online purchases, reported that 28 percent of pre-orders it tracked for the iPhone 5c were for blue phones, 20 percent for pink phones.

What was the least popular color for the iPhone 5c, according to Slice’s data? Yellow, which accounted for 10 percent of the orders.

Hayley Tsukayama

In Germany, meanwhile, a group of hackers claimed to have fooled Apple’s scanner using an artificial finger:

The group claiming to have cracked Apple’s security feature, the Chaos Computer Club, said that all it had to do to trick the sensor was to make a “higher resolution” phony finger, which could be done by pulling a print off glass.

“As we have said now for more than [sic] years, fingerprints should not be used to secure anything,” one of the group’s members said in a blog post. “You leave them everywhere, and it is far too easy to make fake fingers out of lifted prints.”

The group also posted a video showing someone programming an iPhone 5s to recognize one finger, and then using a cover over a different finger that does not appear to be programmed into the phone to unlock the device.

Hayley Tsukayama

The scanner has also raised concerns among lawmakers and privacy advocates, who worry that fingerprint data could be abused:

Sen. Al Franken (D-Minn.) sent a letter to Apple chief executive Tim Cook noting how fundamentally different biometric identifiers are from previous ID methods:

“Passwords are secret and dynamic; fingerprints are public and permanent. If you don’t tell anyone your password, no one will know what it is. If someone hacks your password, you can change it — as many times as you want,” Franken wrote. “Let me put it this way: If hackers get a hold of your thumbprint, they could use it to identify and impersonate you for the rest of your life.”

Franken wants to know more about the technical possibilities of Touch ID and how Apple plans to use it — as well as what diagnostic information, if any, the iPhone 5s transmits about the Touch ID system to Apple and third parties. And he wants assurances that Apple will never share the fingerprint data or the tools needed to get them with commercial third parties.

Another important question is whether Apple considers fingerprint data to be the contents of communication or a subscriber identity under the Stored Communications Act. This is particularly important because content data require a warrant to be released to law enforcement, but a subscriber ID or number needs only a subpoena. Similarly, Franken asks if Apple considers fingerprint data to be subscriber information that the company could be compelled to share by the order of a national security letter.

Andrea Peterson and Hayley Tsukayama

Some users who bought new iPhones have experimented with the scanners in more frivolous ways as well, programming their devices to recognize their toes and their pets’ paws.

The Post's Hayley Tsukayama offers the latest on the newest round of iPhone products and software. (Sandi Moynihan and Hayley Tsukayama/The Washington Post)