Critics may have panned the new iPhones for not moving the needle much, but diehard fans in Asia and Europe still lined up outside stores for the launch.
Reviewers had been somewhat subdued about the new iPhone models, generally saying that outside the new fingerprint scanner on the 5S, they lacked a "wow" factor to differentiate them from the smartphone herd.
"Maybe the age of annual mega-leaps is over," wrote David Pogue, of the New York Times.
(Read more: Why everyone was wrong about Apple)
The iPhone 5C, the cheaper of the two models, disappointed investors and analysts who thought the $500 price tag was still too high to appeal in most emerging markets.
Apple has been unusually tight-lipped about iPhone 5C preorders. In the past, the tech giant has been quick to boast about its high sales during the first few hours its devices became available. The fact that the company has kept mum on the matter so far has led some to speculate that the early pre-order numbers aren't as good as they had been for earlier models.
Other indications suggest the new iPhones are getting a shrug, with the Los Angeles Times reporting the TaskRabbit index, compiled by the San Francisco micro-job site on the number of people hired to wait in line for the latest Apple launch, shows only around 250 were tasked with the queue in all 15 of its markets, compared with around 350 just in San Francisco and New York alone last year.
Despite the underwhelming consumer response in the U.S., Asia and Europe's die-hard Apple fans were enthusiastic.
Hoards of people queued around the block outside stores in Berlin, Paris and London on Friday. One man at the front of the line at London's Regent Street store was reportedly offered £7,000 ($11,245) for his place.
At the biggest Apple store in Asia in Beijing, several security guards kept the line in order to avoid a repeat of the egg-throwing that marred a previous launch. Demand for the iPhone 5S in gold was keen, with the 5C seeing little interest.
(Read more: For Apple, mum's the word on iPhone 5C pre-orders)
"5S is more advanced in technology. 5C is the same as iPhone5. I already have a 5, no need for me to have a 5C," said a sophomore student outside the store. "With the color of gold you can tell right away it's an iPhone 5S."
He didn't think 5,288 yuan (around $860) was expensive, adding he was excited that China had finally become one of the countries receiving the new model in the initial launch round, up from the third round previously.
In Singapore, iPhone aficionados lined up outside the EpiCentre store in the Orchard Road shopping belt the night before the products were released, planning to wait overnight even though the retailer posted a sign saying the 5S was out of stock and only the fingerprint-scanner-less 5C would be sold.
"I just hope tomorrow they will have [the 5S]," David Do, who was near the front of the line, said on Thursday around 7:00 p.m. Singapore time.
"It's just a love for Apple," said Nam Thana, a student in Singapore. He said he didn't have a problem with buying the 5C instead of the 5S. Further along the line, Minh Nguyen said he wasn't sure if he would buy the 5C, but he still planned to wait overnight.
Several said they were planning to buy two phones, with the second for a friend and in one case, for his mother. But they may be doomed to disappointment as an Epicentre employee said sales would be limited to one iPhone per person.
A spokesperson for the city-state's largest mobile operator, Singtel, said the new phones were well-received by customers, with total demand for the iPhone 5S, 5C and 5 exceeding the iPhone 4 models. The company avoided lines by using an appointment booking system; "The gold model was snapped up within 4 minutes of the appointment booking site opening," he said.
Because the cheaper 5C line is still at a premium over most mid-range competitor models, it won't boost volumes as much as an economy-priced unit, but adding multiple price points and colors should expand Apple's audience, Mykola Golovko, senior analyst for consumer electronics at Euromonitor, said via email.
"The 5S line is really aimed at pushing replacement sales, and should do very well especially in markets where iPhones serve as status symbols," he added, noting Euromonitor expects China's iPhone sales to hit 26 million in 2013 before growing to 32 million in 2014.
Apple sold around 31.2 million iPhones in the quarter ended June 30, up from 26 million a year earlier.
—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1