title: How to give each user a free trial period in android
body: <p>I want to publish an Android app with 15 days as a trial period and after that, there will be a one-time subscription charge applicable for the lifetime. I see there is an option in play store developer account for the trial period, so my question is if the user cancels the subscription in the trial period after that is that user will able to use the app? I don't want to change any code for this in my .apk file.</p>