Sales of Apple's new iPhone models - the 5s and 5c - began in earnest Friday around the world.
According to Apple's website, sliver and "space grey" versions of the iPhone 5s are available in 7-10 business days, while consumers hoping to snag a gold iPhone 5s will have to wait until October.
Analysts from Piper Jaffray and ISI predict Apple will sell between 5 and 6 million iPhones this weekend, slightly ahead of the pace of last year's iPhone 5 launch.
"Demand reads are universally positive early on," said Brian Marshall, an analyst at ISI Group. "Now it's just a question of supply."
He cautioned to not read too much into the fact that iPhone 5s gold models were not available online until October.
"Apple likely over-allocated phones to their retails stores to drive traffic and lines and higher margin accessory sales, versus allocating to its online store, retail distribution partners (Wal-Mart and Best Buy etc) and carrier partners (AT&T, Verizon etc)," he added.
Eager consumers around the world braved lines at Apple stores in hopes of securing the new iPhones.
Apple CEO Tim Cook greeted shoppers at the flagship Apple store in Palo Alto, dropping in for about 15 minutes early on Friday morning as sales of the new iPhones kicked off in the U.S.
Demand has been "incredible" and Apple is currently sold out of certain iPhone 5s models or has limited supply of certain 5s models in stores, Apple spokeswoman Natalie Kerri's said.
An Apple rep at the Palo Alto flagship store said the IPhone 5s gold model sold out swiftly Friday morning. The silver 5s sold out at around 1 p.m. ET. The "space grey" 5s model was still available as of 1 p.m. ET, as were the 5c models, the rep said.
The rep said demand and interest matched levels seen at last year's iPhone 5 launch weekend. Roughly 150 people waited in line outside the store as of 1:30 p.m.
Lines began outside the store at 5 a.m. P.T. -- the earliest allowed by the Stanford Mall operator. Before that, Apple fans waited in their cars in the parking lot.
Still, lines were shorter than during previous iPhone launch weekends, according to Ashish Gupta, an executive at Applauze, a ticketing and events app that competes with eBay's Stubhub.
"It's the lack of a new form factor -- a different look, not necessarily a different size," he said.
Gupta has been to every iPhone launch and this morning he surveyed everyone in line outside the Palo Alto store. Apple gives out cards to each shopper in line showing what iPhone model they are waiting for -- to make sure people don't wait for ages and then get inside to find the model they want has sold out.
Gupta said the iPhone 5s gold model was the most popular. Apple handed out no more than 50 cards for this model. After that, there were no more available to sell, he noted.
This suggests that Apple has a limited supply of the gold iPhone 5s models -- something that analysts were concerned about heading into the sales weekend.
The popularity of the gold iPhone also suggests that consumers are yearning for a new form factor, Gupta said. The gold color makes it clear that the owner has the new iPhone, whereas other models may be too similar to the iPhone 5.
"The techies know the new 5s is amazing. But for the masses there needs to be something more obvious," he added.
"There is no issue with supply of the 5c that I can see," Gupta said.
Some people, far from decrying the lines, made a day of it.
New Yorkers Liam Walsh and Allison Lewis took the day off work to grab iPhone 5s smartphones in the morning and a license for their October wedding after lunch. An hour into their wait, opening-day line veteran Walsh was saying the line moved faster than during past launches, drawing an amused look from his fiancé.
"The couple that waits in line together, stays together,'' she said.
Nashville's upscale Mall at Green Hills, hundreds lined up for the new iPhones. Many camped out all night long outside the mall, which opened its doors at 5 a.m. to allow Apple customers to begin forming lines.
Apple workers, donned in blue T-shirts, cheered and clapped as they prepared to open the store at 8 a.m. to begin selling the new phones.
Mike Shepherd, 36, of Nashville, was first in line for a new iPhone 5s. He's a social media coordinator at Nashville-based Griffin Technology, a company that makes iPhone accessories, and he and his co-workers needed to get their hands on one of the new phones. And fast.
"Apple didn't give out free samples," Shepherd said.
Romina Jara, 21, of Murfreesboro, Tenn., was a little farther back in line. She said she had hoped to get the new gold-colored iPhone 5s but workers at Nashville's Apple Store had already passed out enough vouchers for the limited supply of that model. Still, she said, she's excited about the new phone.
"It is all about getting the phone on the first day," she said.
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