Gadgets: iPad as Etch A Sketch
ABC News' gadget roundup this week features the nostalgically fun Etch A Sketch case for the iPad, a USB battery fuel cell charger for smartphones, and HP's newest Spectre XT ultrabook. Click through for more exciting gadget picks this week.

A look at how some IPO stocks have fared
Facebook has filed paperwork for an initial public offering of stock. Its public debut, expected this week, will be the most anticipated tech IPO since Google went public in August 2004.

Android and iOS drive mobile app explosion [infographic]

One year ago, less than 40% of mobile subscribers in the United States had a smartphone. That number has increased dramatically, however; according to Nielsen, one in two mobile subscribers now owns a smartphone. Driven mostly by the rise of Android and iOS, which account for more than 80% of the U.S. smartphone market, 2012 has turned into the year of the app. The average number of apps installed on each smartphone has jumped 28% in 2012, an increase from 32 apps to 41. Smartphone owners are also spending increasingly more time using apps than using the mobile web, roughly 10% more than last year. Nielsen notes that the top five most active apps continue to be Facebook, YouTube, Android

News Summary: Does advertising on Facebook pay?

MORE TO OFFER: Facebook is responding to extraordinary demand and says more stock will be offered in the company's initial public offering.

First Meteor Shower of 2012 Dazzles
The Quadrantid meteor shower, the first major show of shooting stars in 2012, peaks in the hours before dawn on Wednesday. The best seeing should be after the moon sets around 3 a.m. Astronomers say you may see 60-200 shooting stars per hour if the weather is clear.

Mammoth 'Butchered' by Ancient Man
A young woolly mammoth, found remarkably well preserved in the tundra in Siberia, may have been attacked by lions -- but scientists say there are signs it was then butchered by ancient humans.