WhatsApp’s long-awaited voice calling feature is finally rolling out on Android, but getting your hands on it could be tricky. Not only will you need the latest version of the WhatsApp app, but you’ll also need a friend who already has access to the feature.

Originally scheduled for the second quarter of 2014, WhatsApp voice calling arrives almost an entire year late, and it’s likely going to be another few months before it’s available to all 600 million WhatsApp users across all platforms.

For now, you can access the feature with the version 2.11.561 WhatsApp release for Android — that’s the latest release available from Google Play. But don’t think voice calling be there waiting for you when you open the app.

The Next Web reports that to enable it, you first need to receive a call from another WhatsApp user who already has voice calling enabled. Once you’ve received the call, you must then close the app and reopen it.

It’s not the simplest activation process, but it’s one that ensures only a small number of users are able to access the feature while it is in its infancy. If WhatsApp makes it available to all 600 million at once and there are issues, that’s a lot of people left upset.

• ViaThe Next Web