Does Amazon Android app store provide an in-app billing service?

Each store's IAP solution only works with that store.  However, the code can exist within the same APK as long as the correct purchase library is called for the store that the app was installed from. I accomplish this by using a flag, and compile two different flavors of the app - one for Amazon, and one for Google (actually, a few more than that...).  I already have the mechanism in place to handle linking to the correct app store using the Android Market Manager library (https://github.com/TimMackenzie/AndroidMarketManager) so I just piggyback on the market selector flag. Amazon's IAP solution is out of beta - I just released an app update using it.

Hi, my name is Vítor and I work for Aptoide (http://www.aptoide.com/). You can reach several markets and publish your apps in most of the app stores using one unique billing SDK. Open-IAB it’s an Open Source Billing SDK that allows you to publish and distribute to several Android App Stores: Aptoide, Google Play, Amazon Store, SlideMe, Nokia Store, Samsung Apps, Yandex.Store, Appland, AppMall and Fortumo. In Aptoide you publish for free and if you use Open-IAB (Billing SDK) we give you a 75% margin for in-app purchases and paid apps. If you want to enrol our Certified Publishers Program for free go to: https://www.aptoide.com/account/new-user?type=publisher I would be very glad to have you on board, to discuss this matter or even to answer any doubt you might have. Disclaimer: I am currently an employee of Aptoide!

Amazon requires that you use their in-app billing solution for freemium apps published in their store.

Does it mean Amazon appstore on Android phones also not support apps implementing Google's IAP?