https://arstechnica.com/gadgets/2020/01/apple-releases-ios-13-3-1-and-macos-catalina-10-15-3/

Today, Apple released updates for its operating systems for iPhone, iPad, iPod touch, Apple Watch, Mac, HomePod, and Apple TV devices. iOS 13.3.1 is the most substantial of the updates, but they are all incremental updates that fix bugs or address user complaints or privacy concerns.