Apple's new iPad Air got off to a fast start this weekend, according to measurements of its online activity, which was twice the combined shares of 2012's then-new fourth-generation iPad and iPad Mini tablets.

Boston-based Fiksu, an iOS and Android app marketing firm, said that as of Monday, the iPad Air accounted for 0.72% of the iPad traffic that accessed its clients' apps. That was almost five times the 0.15% of the fourth-generation iPad after its first three days, and over three times the 0.21% of last years' original iPad Mini.

The iPad Air's online usage was double the combined total (0.36%) of last year's new tablets at the same point after their debut.

Both the iPad Mini and the fourth-generation iPad went on sale Nov. 2, 2012. This year, Apple launched only the 9.7-in. iPad Air, saying it would start selling a refreshed iPad Mini -- one with a higher-resolution Retina-style screen -- later this month.

Another change this cycle: Apple kicked off sales of both Wi-Fi-only and Wi-Fi-plus-cellular models simultaneously. In 2012, the latter lagged the former by two weeks, debuting Nov. 16.

Apple has not announced opening-weekend sales for the iPad Air -- which remains widely available, making good on analysts' expectations that supply would match demand -- as it did last year when it cited 3 million sold after the first three days.

But while Fiksu's data hints at double the sales -- in other words, approximately 6 million -- it's far from a guaranteed indicator, coming as Fiksu's numbers do from app usage, which identifies activity such as app launches and in-app purchases, not the number of individual tablets.

The iPad Air's initial usage share of all Apple tablets hinted at sharp sales over the opening weekend. (Image: Fiksu.)

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is [email protected].

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