But here’s what Nokia didn’t disclose: the price of the device, a specific release date and the carriers that will offer it. The omissions underscore the importance – and difficulty — of keeping pace in a smartphone market where phones have to be updated every year.

When Apple releases a new iPhone, it shows all of its cards, and that helps attract attention from consumers and software developers. At the iPhone 4S launch last October, Apple had the price ($199 in the U.S.), the carriers (AT&T, Sprint, Verizon Wireless, and Apple retail stores) and the availability date (preorders from Oct. 7). It also listed the six countries outside the U.S. where the phone would be available and the 22 additional countries where it would be sold in later that month.

Although a person familiar with the matter said Nokia could release additional details on price and availability in a week, the lack of specificity on launch day was an issue during the question and answer session and contributed to a 13% drop in the company’s Helsinki-listed shares.

When the first questioner asked when he could get one of the phones, Mr. Elop reminded participants that the company wasn’t announcing specific launch dates but said it would be made available in select markets during the fourth quarter. The next journalist asked if the Lumia would be sold in China. Mr. Elop again declined to answer, but said that China remains an important market for the company.

IDC analyst Ramon Llamas said while he was impressed by some of the phone’s new technology, such omissions harmed the launch. “There are some key questions that have not been answered,” said Mr. Llamas, who attended the event. “They did not talk about price or who is going to get it.”