Скачать или смотреть What's New on iOS 13.3.1 And How to install it on your iPhone(6s,6s+and above)

Apple has released iOS 13.3.1 for the iPhone. While mostly focused on a number of bug fixes, if you have an iPhone 11 series device, this update gives you greater control over the data collected by the U1 Ultrawideband chip with a new setting.

The iOS 13.3.1 has some important bug fixes for the iPhone.
Fixes an issue in Communication Limits that could allow a contact to be added without entering the Screen Time passcode
Addresses an issue that could cause a momentary delay before editing a Deep Fusion photo taken on iPhone 11 or iPhone 11 Pro
Resolves an issue with Mail that could cause remote images to load even when the “Load Remote Images” setting is disabled
Fixes an issue that could cause multiple undo dialogs to appear in Mail
Addresses an issue where FaceTime could use the rear facing ultra-wide camera instead of the wide camera
Resolves an issue where push notifications could fail to be delivered over Wi-Fi
Addresses a CarPlay issue that could cause distorted sound when making phone calls in certain vehicles