New York (CNN Business)One of the most surprising announcements from Apple's Worldwide Developers Conference keynote on Monday wasn't a new feature for its own customers — it was something new for Android and Windows users.

As part of its unveiling of iOS 15, Apple (AAPL) said users of other operating systems will be able to join FaceTime calls when invited via a link sent by an Apple user. The announcement about FaceTime was among a slew of other software updates introduced for the iPhone, iPad and other Apple (AAPL) products.