FORTUNE -- The early preference for the iPhone 5S over the iPhone 5C has faded a bit in the week since their release, according to a report issued Friday by Localytics, a Boston-based mobile analytics firm.
As of Sept. 22 Apple (AAPL) was selling 3.4 units of the iPhone 5S for every 5C. By Sept. 26 that ratio had contracted to 2.9 to 1.
Localytics also found regional differences in the 12 cities it studied. San Francisco -- a hotbed of app developers and other early adopters -- showed the strongest preference for the more advanced 5S (85% vs. 15%).
Philadelphia, at 72%, showed the least. The company did not offer a reason why.
Below: The 12 cities ranked by percentage of active iPhones. In general, the bigger the city, the more popular the new models. The exception is San Francisco, which came in third even though it is the 11th largest market.
Praised for trying to make Apple's iOS devices accessible to people with disabilities
At a Stevie Wonder tribute in Los Angeles' Echo Park last Saturday, the 22-time Grammy winner took the stage briefly to sing a few bars and talk to the audience about Sept. 11, the power of love and Apple's (AAPL) Steve Jobs:
"And I want you all to give a hand to someone that you know whose health is MOREPhilip Elmer-DeWitt - Sep 15, 2011 7:04 PM ET
By Sunday, the new tablets were selling in China for up to 105% over their sticker price
The staff manning the huge crowd that mobbed Apple's (AAPL) Fifth Avenue Store Friday estimate that as many as half the iPads sold that day were being bought for re-sale overseas.
It's a familiar pattern. In September, the New York Times ran an investigative report detailing how Chinese customers were lining up to buy pairs MOREPhilip Elmer-DeWitt - Mar 14, 2011 8:02 AM ET
Some of the bogus Apple (AAPL) hardware recovered by Los Angeles Port Police. Estimated street value: $10 million.
"This was a well-funded operation, and the counterfeits looked very authentic," chief Ron Boyd told the L.A. Times. Buyers might not have discovered they'd been bilked, he said, until they got home and tried to hook the devices up with iTunes.
Also on Fortune.com:Inside Beijing's iPhone black market Holiday crime spree targets Apple Smash n' MORE Philip Elmer-DeWitt - Feb 8, 2011 6:06 AM ET
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