As the finish line for the 2011 holiday season comes into focus, promotional activity is heating up with big digital brands such as Amazon, Groupon and eBay trying to drive uptake of their services – which all have significant mobile components – via special offers.

Mobile deals will play an important role for PayPal next year as it continues to build a multifaceted retail technology solution to help retailers address the pain points in their businesses.

PayPal saw a 516 percent increase in global mobile payment volume on Black Friday in 2011 compared to 2010.

EBay has partnered with food truck Kara’s Cupcakes for the Happy Holiday Hotspots campaign to deliver sweet treats and let consumers bypass the long Black Friday lines by buying via eBay’s mobile application.

EBay has introduced two new interactive store windows with the aim of making it easy for holiday shoppers to donate toys by scanning a QR code.

EBay confirmed that 2011 will be its largest mobile shopping season to date with an expected $5 billion in mobile sales, driven in part by the holidays.

EBay has partnered with designer Jonathan Adler to let consumers shop its new storefront and interactive store windows via their mobile devices.

The volume of payments made via PayPal from mobile devices will total more than $3.5 billion in 2011, with the company expecting a significant jump in mobile payments during the upcoming holiday shopping season.

EBay’s StubHub has teamed up with Sprint to let fans buy and sell tickets to college and pro football games via their mobile devices.

Mobile will play a big role for eBay as it migrates to an open ecommerce ecosystem that will enable developers to create new services and apps that enhance online and mobile shopping.