Last month, X CEO Linda Yaccarino confirmed that video calls would be coming to the app. Now, the new code in the X app shows that audio and video calls will be supported. However, this feature won’t be available to all X users — only those with an X Premium membership.

The feature will allow X users to receive both audio and video calls from other verified users, from people they follow, or from people in their address book, depending on their choice.

“Take messaging to the next level with audio and video calls. Enable this feature, and then choose who you’re comfortable using it with,” the feature description reads.

The other lines of code refer to a warning that appears when someone tries to send a DM to another app user that explains that “audio and video calling is a premium feature” and encourages them to “subscribe to gain access.”

This means that users will have to pay for X Premium, which includes a number of updated features: verification, reduced ad load, the ability to edit posts, support for longer posts, priority ranking in search and conversations, and more.

So far, X has not been able to make a convincing case for X Premium, as independent research has shown that the company has only sold approximately 1 million subscriptions. Musk recently stated that the app has 550 million monthly active users.

In comparison, Snapchat+’s premium subscription has surpassed the 5 million user mark . Meanwhile, analysts predict that Meta’s subscription, Meta Verified, will have 12 million subscribers early next year.