Global shipments of Wi-Fi-enabled cell phones are expected to double between 2009 and 2011, at least partially due to the emergence of a slew of smartphones with Wi-Fi capabilities, according to an analyst at ABI Research in New York.

Analyst Michael Morgan said he expects about 300 million handsets that provide dual wireless capability for cellular and Wi-Fi to ship during 2011, up from about 144 million expected to ship this year.

Morgan added that he expects about 85 million Wi-Fi-capable smartphones to ship globally this year -- of 170 million total smartphones.

The Wi-Fi-capable smartphones include Apple Inc.'s iPhone and other popular offerings.

Morgan noted that the number of smartphones shipped is expected to grow by about 20% each year for the next several years, and predicted that fully 90% will have Wi-Fi capability by 2014.

"A doubling of Wi-Fi enabled cell phones in two years is ridiculously high," Morgan said. "Wi-Fi has become a must-have item much as Bluetooth did earlier."

Part of the value of having a Wi-Fi handset these day is that the number of hot spots in coffee shops and other buildings is exploding while more and more homes and even planes support the technology, he noted.

Eight U.S. Airlines now offer Wi-Fi access on more than 500 flights, with the number expected to grow to entire carrier fleets in two years.

Following AT&T's lead, Verizon Wireless recently made 30,000 Boingo Wireless Wi-Fi hot spots available to some 9 million of its residential customers on certain plans.

Morgan said Verizon is "warming up to Wi-Fi" and can be expected to support more smartphones and handsets with dual mode capability for Wi-Fi.

Even AT&T was at first leery of Wi-Fi, fearing it would take traffic off from their cellular networks, Morgan said. But AT&T was "thrown into the [Wi-Fi] pool by the iPhone" after it first surfaced two years ago, he added.