Hi, I need some clarification :- Is it possible to uniquely identify each user who has downloaded an Android App from Google Play /Market Store? Is it possible to uniquely identify the user device as well? Say for e.g. for userA a different id (or sequence no) for the App1 downloaded onto his android phone and a different id for App1 downloaded onto his android tablet? I am looking for a concept of unique identifier to be allotted to each user downloading the App. If there is a feature/API/lookup which GooglePlay provides by default then it is better to leverage that instead of building one . Any comments/pointers will be appreciated. Thanks.