Less than 24 hours after Apple (NASDAQ:AAPL) released the new iOS 7 to the public on Wednesday, the revamped version of the mobile operating system was installed on 18 percent of iOS devices, according to data released by Chitika, an online ad network.

In a bid to determine the success of iOS 7, Chitika tracked the adoption rate of iOS 7 across all iOS devices. It examined a sample of millions of North American iOS-based online ad impressions from within the Chitika Ad network, between Sept. 18 and Sept. 19.

The growth rate of iOS 7 was then compared to total iOS web usage using a time series to demonstrate the rate of adoption of the new OS. For comparison, Chitika overlaid the 24-hour iOS 6 adoption data, which was recorded last year.

According to Chitika, the pre-release iOS 7, or iOS 7 betas, showed low levels of usage, but following iOS 7’s public release on Wednesday, adoption levels soared despite high loads on Apple’s servers.

About 24 hours from the start of the public rollout of iOS 7, adoption rates reached levels above 18 percent, beating the adoption rates of iOS 6 (15 percent) in the same time period last year. On the other hand, the iOS 5 took five days to reach a 20-percent adoption rate.

By comparison, Google (NASDAQ:GOOG) reported that, as of Sept. 4, the adoption of Jelly Bean, which was released in July 2012, accounted for about 45 percent of the Android ecosystem. According to Chitika, if the current trend continues, the iOS 7 will be able to surpass that mark very soon.

Meanwhile, another report from Mixpanel, a mobile analytics firm, said that iOS 7 was installed on 36 percent of Apple devices in the first 24 hours after it was made available to the public. And, Mixpanel is tracking the progress as it goes, so users can keep checking it in future.

Android’s Jelly Bean (all versions), on the other hand, still accounts for only 57 percent of traffic on the Mixpanel network, more than 450 days after the first version’s launch.