Apple announced that it sold 300,000 iPads on day one, but if you want to get a real-time update of iPad sales — to turn a marketing slogan — there’s a website for that! The Chitka advertising network has set up a page that attempts to estimate the number of iPads sold based on unique visits to its advertising network.

The company’s methodology, while not 100% accurate, effectively measures how many iPads have accessed the Internet.

Here’s what they do: Every unique iPad that comes through the Chitka ad network is counted. That number is then multiplied by how much of the Internet Chitka is seeing at any given time. The results are added in real-time to its webpage.

In addition to estimating the number of iPads sold, Chitka also calculates the location of these devices. So far, California is leading the pack with the most iPads — nearly 20% of all iPads online come from the Golden State.

At the time of this writing, Chitka reported that 285,000 iPads have been sold. Although that estimate is certainly less than the official numbers, it appears to accurately measure how many units are online.

As crazy as it may sound, there might be some people out there that aren’t using their iPads to surf the web. Who these people are, I don’t know — but there are apparently some of them.

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Tags: chikta advertising network, ipad, ipad sales, ipad tracker