Hi, I am building a game and would like to use the user id returned by the IAP SDK as a unique identifier to create accounts in my own internal API (to store game progress, scores, etc). Does anyone know if there would be problems with this idea if I wanted to also link this account across different Amazon devices (ex. Kindle HD, Kindle Fire TV, etc)? Several forum posts seem to suggest that the IAP user id would be the same for the same user and application, so I guess the question is if its possible to upload different APKs to represent the different devices in a single application or if it would require setting up different applications. If it requires different applications, I assume that the user id provided by the Login SDK would be more suitable? Thank you for your time!
Hi Davespacey, Thank you for reaching out. Yes, you can safely use the userid returned by IAP SDK to identify the user in case of Kindle devices. The id would be unique for the app (the one you create in Developer Console) and the user (registering the Kindle with same Amazon account). If your app needs to upload multiple APKs for different Kindle devices, that would not be any problem since all the apks under the same app would be treated as same. We actually identify the app buy it's id or package name, not by the apk. Login with Amazon SDK also can be used for the same purpose. But that would give your user one extra UI for authentication which will not be frictionless.