Traditionally, Apple’s iTunes App Store has been the big winner in terms of revenue for app developers. But for one developer, that’s not the case. It’s the Amazon Appstore that’s helping pull down more money.

At least, that’s in revenue generated by each individual user, and it’s for developer TinyCo, which has games on all three platforms. TinyCo is finding that, for its games, Amazon is solidly better than iOS in bringing in per-user revenue; something like 80 percent better, in fact. Broken down, the Kindle Fire is 43 percent better for revenue than the Apple iPad, as TechCrunch reports.

That’s a pretty substantial margin and a big difference between the devices. TinyCo isn’t the first to say that the Amazon Appstore is bringing in more revenue for developers than Google’s marketplace, but it’s notable that the developer is finding more success with Amazon over Apple’s iTunes App Store, which traditionally is tops in revenue for developers.

Google Play isn’t doing terribly for TinyCo, either, it’s worth noting. The developer says it’s making about 83 percent of revenue per user on Android smartphones, which is higher than what Flurry Analytics found earlier this month when analyzing the three major app stores.

TinyCo’s data is interesting because the developer has managed to have top-grossing apps in all three app stores, which is significant given the fact that Amazon’s in-app purchasing capabilities haven’t been available for very long. It’s an isolated case, to be sure, but TinyCo’s findings demonstrate what seems to be a larger trend: Google is potentially being out-competed in app marketing by its more experienced, better-entrenched rivals.

There are other factors to consider. Google is dealing with less lucrative international markets in its averages while Amazon’s Appstore is only available in the U.S. Also, Amazon and Apple have huge established user-bases with credit card information on file, and Amazon may still be riding the wave from when the Kindle was first introduced. However, Google is aware of the fact that it needs to step up its game in terms of Google Play. During an earnings call last week, Google CEO Larry Page acknowledged that Google needs to streamline the Android experience to improve it.

The fact that Amazon seems to have a successful market might be good for Google because it can help give it goals to hit and a model from which to learn. It’s clear that Android’s growth is powerful but won’t last forever unless Google continues to improve.

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