Will your app get rejected if it has code for Google IAP, but that code never gets called on an Amazon device? At the moment, we have code for Google IAP in the app (not called on Amazon devices, and at the moment, not even called on our public google builds -- only internal test builds), and plan to add support for Amazon IAP later, but just support the free mode on Amazon in the meantime.
We're trying to have a single build/binary, and also be mindful of the various app store rules. We're hoping that we don't end up needing one custom build per ecosystem - a mess of extra engineering/QA/etc.
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