Determine date (or version) that app was purchased from Google Play Store - equivalent of iOS appStoreReceiptURL
Getting Time and Date Install
You can get the time and date of the first install of the app by using
long installTime = context.getPackageManager() .getPackageInfo("com.some.package.name", 0) .firstInstallTime;And the version with
PackageInfo pInfo = getPackageManager().getPackageInfo(getPackageName(), 0);version = pInfo.versionName;Unfortunately this date will reset whenever the app is uninstalled and reinstalled.
If you go with
PackageManager pm = context.getPackageManager();ApplicationInfo appInfo = pm.getApplicationInfo("app.package.name", 0);String appFile = appInfo.sourceDir;long installed = new File(appFile).lastModified();you will also find out the date when an application was installed, but the time returned will change every time the package is updated.
Suggested Solution
A solution could be an online database for your application, where you can store each user's ID using AccountPicker, their first-time-install with the methods described above and use them at login. You can also use the App Licensing Service.
http://developer.android.com/reference/android/content/pm/PackageInfo.html#firstInstallTime