In a recent revelation, X CEO Linda Yaccarino announced that the app, formerly known as Twitter, is expanding its offerings into an “everything app,” including the addition of video calls. However, new insights from the X app’s code indicate that both audio and video calls will be exclusively available to X Premium members.

Tech veteran-turned-investor Chris Messina discovered these developments within the X app’s code. The feature is set to enable X users to opt-in to receive audio and video calls from Verified users, people they follow, or contacts in their address book, depending on their preferences.

The feature’s description emphasizes its opt-in nature, stating, “Take messaging to the next level with audio and video calls. Turn the feature on and then select who you’re comfortable using it with.”

Additionally, lines of code mention a warning message that will appear when users attempt to direct message (DM) someone on the app, explaining that “audio and video calls are a premium feature” and encouraging users to “subscribe to gain access.” This means that access to audio and video calls will require a subscription to X Premium, which was previously known as Twitter Blue. X Premium offers several enhanced features, including verification, reduced ad exposure, post editing capabilities, support for longer posts, priority in search and conversations, and more.

To date, X has struggled to make a compelling case for X Premium, with independent research suggesting that the company has sold only approximately 1 million subscriptions, as tracked by researcher Travis Brown on GitHub. For context, X’s owner, Elon Musk, recently reported that the app boasts 550 million monthly active users.

Comparatively, Snapchat’s premium subscription service, Snapchat+, has recently surpassed 5 million users, while analysts anticipate that Meta’s subscription offering, Meta Verified, will have 12 million subscribers by early next year.

Since Elon Musk’s takeover, X no longer responds to requests for comment, offering only automated responses to incoming press inquiries.