The feature was announced alongside the Quest Pro's Touch Pro controller at Connect 2022 in October 2022. This is a feature that developers can enable in their apps, called multimodality.
It's currently possible to build Quest apps that support both hand tracking and controllers, so you can pick up or put down the controller at any time to switch between the two modes. But when the controller is put down and hand tracking starts, there is a delay, the controller disappears and the tracking stops.
Using the multi-modal feature, controller tracking is continuous, enabling instant switching and mixing of hands and controllers. For example, this would allow single-handle games like GOLF+ and Walkabout Minigolf to simultaneously track the other hand.
Meta CTO Andrew Bosworth demonstrates the multimodal feature in action in a video.
Multimodal will be rolling out as an "experimental" option, which generally means it's not currently available on the Quest Store or App Lab. As an experimental option, it only supports the Quest Pro, but when it launches publicly, it will also support an unspecified "other devices and controllers."
This could include the upcoming Quest 3. According to Meta's CTO, the Quest 3 is constantly running controller-free hand tracking fused with infrared LED tracking when the controller is in use.
Meta also lowered hand tracking latency for Quest 2 and Quest Pro in the v56 Quest software update. Version 56 also adds a new Fast Motion Mode (FMM) that developers can enable, which Meta says improves tracking of "fast motion" that's common in fitness and rhythm apps.
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