Google is set to release the mobile wallet Android Pay on Sept. 16, but for those who are unable to wait for its official release, there's some good news: Android Pay can be used even now on smartphones.

Google Play Services version 8.1 is already popping up on some Android smartphones. Users who are among the lucky few to have the updated version will be able to access a hidden activity feature in the app to get started on Android Pay.

In essence, Google Play Services 8.1.03 has Android Pay activity concealed inside the app. For those wondering what we mean by activity, it is a starting point for views or an app inside an app. One is usually able to access the activities of any app by opening the app, thereby beginning the activity.

Alternatively, the easiest way to access hidden activities would be to download an activity launcher app such as Activity Launcher or Nova Launcher.

Since Android Pay is currently not available as an app with its own APK, it would be simplest to access the same through Google Play Services 8.1.03 in this manner. The only hurdle would be getting access to the latest Google Play Services version. However, several APKs for Google Play Services can be found online on APK Mirror, but remember to download the appropriate APK for your phone from the list.

To check the correct version of Google Play Services, navigate to Settings > Apps > Google Play Services. Search for the last three numeric in the brackets.

Once the right APK for your Android handset has been sorted from the list, download and install the same. Once installed, launch Android Pay from within the Google Pay Services and you're good to go.

Google will guide you on how to add your credit card details so you can start using Android Pay to make payments at compatible terminals. If Android Pay does not work, you can always wait for the official release, which is about a week away.