By JOSEPH PISANI and ANNE D'INNOCENZIO
AP Retail Writers

NEW YORK (AP) - Like Black Friday, Cyber Monday is spreading out into a week-long shopping fest, with Amazon, Walmart and Target calling it "Cyber Week."

Still, Monday is expected to be the biggest online shopping day in U.S. history, according to Adobe Analytics, which tracks online sales at 80 of the top 100 retail sites.

Other things to know on Cyber Monday:

BIG EXPECTATIONS

Online spending is expected to reach $7.8 billion on Monday, an 18 percent increase from a year ago, according to Adobe Analytics. About 20 percent of the day's spending is expected to happen late Monday, starting at about 10 p.m. Eastern, when shoppers are home from work and rushing to catch some deals before they're gone.

SMARTPHONE SHOPPING

Instead of trekking to the mall, more people are picking up their phones. More than $2 billion in sales are expected to take place through smartphones on Monday, according to Adobe Analytics. On Black Friday, more than $2.1 billion was spent using smartphones, a record number.

Retailers have spent money updating their apps, making it easier for people to browse and pay, says Charlie O'Shea, lead retail analyst at Moody's.

At Macys, for example, mobile sales are expected to hit $1 billion for the first time by year end, said Macy's CEO Jeff Gennette.

AMAZON STILL TOPS

Amazon is expected to dominate - grabbing as much as half of all online sales by the end of the year, according to consulting firm Bain & Co. But that doesn't mean others aren't putting up a fight. Target, for example, is temporarily offering free two-day shipping for the holidays by dropping its usual $35 minimum purchase requirement. Amazon responded by dropping its $25 minimum, but Walmart is still sticking with its $35 requirement.

Kathleen McKenna of Manahawkin, New Jersey, says half of her shopping this holiday season will be online.

Her plans for Cyber Monday: "I'm shopping off of my son's wish list on Amazon," she says.

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