In iOS 26.2 beta 3, Apple is laying the groundwork for a future option that will let iPhone users in Japan choose a different default voice assistant. Right now, a press and hold gesture on the Side Button only activates Siri, but there are multiple references to new Side Button behavior in the beta. The wording suggests that the iPhone will permit users to choose a different app to activate through the Side Button, though Apple has confirmed this will be limited to iPhone users in Japan.