Preparing for iPhone 4 launch day (FAQ)

It's that time of year again when throngs of people line up, sometimes days in advance, for the latest and greatest version of the Apple iPhone.

Thursday is the official release date for the iPhone 4. And from the looks of things, this year could be the biggest of all iPhone launches.

AT&T says that demand for the iPhone 4 is 10 times what it was for the iPhone 3GS. And Apple says it took 600,000 preorders for the new phone through its sales channels.

If history is any indication of what to expect, initial sales of the iPhone 4 are likely be a doozy. Apple sold more than 1 million iPhone 3GS smartphones the first three days it was on sale. The original iPhone sold about 270,000 units during its first weekend in June 2007, while the iPhone 3G sold around 1 million when it launched in July 2008.

Apple CEO Steve Jobs called the iPhone 4, which is the fourth generation of iPhone, the "biggest leap since the original iPhone" was launched in 2007. With a new homegrown processor like the one used in the iPad, a bigger battery, a 5-megapixel camera that can record video in high definition, and a new FaceTime video chat application, the iPhone 4 is expected to be a hotter device than all previous iPhones.

Unfortunately, for customers waiting to get their hands on the new phone, there are already signs that supply may not keep up with demand. On Tuesday, AT&T announced that only preordered iPhone 4s will be in stock in its retail stores Thursday. Anyone looking to buy an iPhone 4 at an AT&T store without having preordered the device will have to wait until June 29.

AT&T's preordering system also crashed over and over on June 15, the day the iPhone 4 was made available for preorder. Potential customers attempting to buy the phone saw error messages as they tried to process their orders.

So what is an expectant iPhone 4 user to do? Check out this FAQ to get a better handle on what will be happening on launch day. For updated information from AT&T, the company suggests checking out its Facebook page.

What happens if I preordered my device?
First of all, lucky you. If you were able to successfully preorder an iPhone 4 via Apple or AT&T then you should check your e-mail confirmation to find out when you can expect it to arrive. Depending on what you chose, the device will either be waiting for you at the store you picked, or it will be shipped directly to your house. AT&T said they are on track to deliver preordered devices. They are sending e-mails when the devices have shipped and for customers picking up their devices at the store, local store reps will be calling to let you know when it's available for pickup.

Will I have to wait in the same long line as everyone who didn't preorder a phone?
No, if you've placed a preorder to be picked up in store, there will be a separate line for you to stand in--you won't have to wait behind people who haven't reserved one ahead of time.

Why are some people receiving their iPhones before Thursday?
Some customers were unexpectedly shipped their iPhones on Tuesday. Meanwhile, there have been reports that some customers who preordered their iPhones will be receiving them a day earlier than Apple originally planned--on Wednesday instead of Thursday. Apple has not offered an explanation. It could be that FedEx is ahead of schedule, or that Apple is strategically trying to spread out the initial activations of the new phones. The activation process, when millions are trying to attempt it simultaneously, has in the past caused a major disruption to first-day iPhone sales.

Can I go to a store to pick one up on the first day if I haven't preordered yet?
It depends. AT&T announced on Tuesday that only preordered iPhone 4s will be in stock at its retail locations on Thursday. Anyone looking to buy an iPhone 4 at an AT&T store without having preordered the device will have to wait until June 29.

Apple did not return phone calls to confirm its policy, but store representatives in New York City and San Francisco said they expect to have iPhones available for sale even without preorder.

That said, demand is high for the iPhone 4 and it's recommended that you arrive very early to ensure you'll get one. Apple stores are opening at 7 a.m. on Thursday and 8 a.m. on Friday.

What are the chances that Apple or AT&T or any of these other stores run out of iPhones?
Apple took 600,000 preorders on the very first day the phone was available for preorder last week. But that doesn't mean you can't try to get a phone by walking into a store that day. Apple keeps a separate stock of phones for walk-in customers. The company is careful to say that supplies are limited and phones will be available on a first-come, first-serve basis, but they have historically ordered enough to accommodate many people on the first day.

If you're not able to make it on Thursday to a store, you can certainly try over the weekend, but it's highly likely that pickings will be slim. In previous years, Apple has run short on certain models of the phone. For example, last year it ran out of the white version of the 16GB iPhone 3GS.

One Apple salesperson at the Upper West Side Apple Store in New York City said he expects the iPhone 4 to outsell the iPhone 3GS, which went on sale a year ago. Based on that assumption, he said that stores are likely to sell out the first day. Apple will continue getting shipments every day. But he said that the phones will likely go quickly and customers could face lines for up to two weeks for the device.

"It's going to be at least a couple of weeks before you can just walk in and buy one," he said. "But keep it in perspective. It's a phone. And if you want one, you'll be able to get one."

Fueling the fear of a potential shortage is the fact that Apple has had a difficult time keeping up with demand for the iPad, which went on sale earlier this month.

If I try to preorder right now, when would I get it?
AT&T is no longer accepting preorders. Apple.com says preordered iPhones ordered today will not arrive until July 14.

Why is the only option to preorder a black 32GB or 16GB iPhone 4?
Neither Apple nor AT&T has answered questions about when the white version will be available. For now, Apple.com says it will arrive "later this summer."

Are there any other retail options for buying the iPhone 4 if I don't want to deal with the Apple store or AT&T?

This year there are more options than ever for places to pick up an iPhone on launch day. Best Buy, Wal-Mart, and Radio Shack will have the iPhone 4starting Thursday. But be warned, it's almost assured that none of them will have nearly as many iPhone 4 units in stock as Apple or AT&T. A Best Buy representative said Wednesday the retailer took a lot of preorders and, depending on the store, some of them will only have units for customers who reserved in advance. Best Buy recommends checking with your local store for availability.

This story was updated at 10:10 a.m. PDT with more information about Best Buy's iPhone 4 availability.