The prerequisites for each function are as follows:
1) APP to APP (OEM App to Alexa) :
iOS version:the OEM App version is 3.12.0 or later;
Android version:the OEM App version is 3.18.0 or later.
2) APP to APP (OEM App to Alexa):
iOS version:not currently supported;
Android version:the OEM App version is 3.18.1 or later.