get app version android
PackageManager manager = this.getPackageManager();
PackageInfo info = manager.getPackageInfo(this.getPackageName(), PackageManager.GET_ACTIVITIES);
Toast.makeText(this,
"PackageName = " + info.packageName + "\nVersionCode = "
+ info.versionCode + "\nVersionName = "
+ info.versionName + "\nPermissions = " + info.permissions, Toast.LENGTH_SHORT).show();