Apple released the third public beta for iOS 12.4 on the afternoon of May 28. The update prepares iPhones for the launch of Apple Card later this summer, along with packing a bunch of bug fixes and performance improvements. Apple has released iOS 12.4 beta 3 to developers for testing. The build number is 16G5038d.

If you want to upgrade to this version:

Step 1 Connect your iDevice to PC with a USB cable and launch 3uTools.

Step 2 Navigate to Flash & JB → Easy Flash and select iOS 12.4 beta3. After you click Flash, there will be a popup reminder and please read it with caution. If you want to save your data, please check the box "Retain User's Data While Flashing".

Please back up your iDevice regularly just in case.

Step 3 Keep a good connection and internet while flashing, wait patiently for around 5 to 10 minutes. Your device will be restored to iOS 12.4 Beta 3 after reboot.