For 45 days, from mid-January to the end of February, the folks at Flurry analytics ran an interesting experiment.

They found a basket of top-rated apps that are available for the same price on three major app stores — iOS, Android and Amazon — whose revenue was generated primarily by in-app purchases. Then they compared the revenue generated by those apps for the developers who created them. The results are shown in the chart at right.

Setting the revenue generated on the Apple (AAPL) App Store at 100%, it found that Amazon’s (AMZN) apps generated 89% per active user and Google’s (GOOG) Android apps 23% relative to iOS.

“Amazon, who forked Android in order to put consumers into their own shopping experience on Kindle Fire, is showing its commerce strength, already delivering more than three times the revenue in its app store compared to what Google generates for developers,” writes Peter Farago on the Flurry blog.

“As markets mature, rational economic behavior emerges,” he adds dryly. “Based on revenue potential, we expect to see increasing numbers of developers support Amazon.  We also believe that companies such as Samsung, the leading Android-supporting OEM, could also consider emulating Amazon’s move to fork Android. “