I can't download it from the Play Store either... but it didn't tell me that it was because I wasn't part of Google Plus... I even tried a few Google accounts and different browsers (in case addons were blocking something necessary). I guess I will pull out my unused Windows Phone.

The error I got:

Sorry - nothing to see here.

There may be several reasons: The app you’re looking for doesn't exist or the app developer is not currently running a test or you are not eligible to participate in the testing program. If you received the link to this page from someone, we recommend you contact them for more information.