Owners of Meta's AI glasses must now pay a monthly fee of $19.99 to use "Conversation Focus" for more than three hours a month, a feature that was previously free. Meta says users who hit the "free monthly usage limit" must wait for their free hours to refresh each calendar month unless they subscribe. A Meta spokesperson said the move is part of experiments with offering subscriptions for some features while keeping core services free. Meta's plans to test "premium" subscription experiments across Instagram, Facebook and WhatsApp were first revealed in January, and the firm later confirmed its tests would include trialling paid access to expanded AI features on its smart glasses. A Meta spokesperson told the BBC on Thursday that users would still have access to other built-in AI features, such as live translation and its voice assistant, without a subscription. Subscribers to Meta One Premium can use Conversation Focus for up to 15 hours each month, but Meta One subscriptions are only available in some countries, not including the UK. One user wrote to Meta Ray-Ban product lead David Woodland that "putting Conversation Focus behind a paywall feels wrong."