One week after launching the previous iOS 13.4 beta, Apple's got another release ready for testing.

iOS 13.4 beta 3 and iPadOS beta 3 are now available to registered developers (via MacRumors). The update can be downloaded over the air or you can load it manually by going to Apple's Developer Center on the web.

The update to iOS 13.4 brings with it several changes, some big and some a little smaller. An updated toolbar in the Mail app moves the delete icon further from the reply icon, making it less likely that you'll accidentally delete a message, and it also adds folder and compose icons.

There are nine new Memoji and Animoji stickers in iOS 13.4, too, as well as new controls for calls and third-party navigation apps in CarPlay. Speaking of cars, the update also includes hints at a CarKey API, which could allow you to use your iPhone to lock, unlock, and start a vehicle over NFC.

Other notable improvements of iOS 13.4 include iCloud Folder sharing, which lets you share folders in your iCloud Drive with other people, and a Settings section in the TV app that'll give you control over streaming and downloading video over Wi-Fi and cellular. These settings also include a Data Saver setting for folks on limited data plans.

Also rolling out today is watchOS 6.2 beta 3 (via MacRumors). This update includes in-app purchases for Apple Watch apps in the App Store and also hints at the same CarKey API that's in iOS 13.4.