Apple released the fourth beta for iOS 11.2.5 to developers and public beta testers. It comes only one day after the official release of iOS 11.2.2, iOS 11.2.5 Beta 4 does not seem to introduce any major features at this point. Rather, it appears to bring standard bug fixes and under-the-hood improvements, one of which is reversing the loud sounds that appeared in iOS 11.2.5 beta 3.

Before you begin, make sure you back up your iPhone or iPad. While the beta process is fairly straight forward, any time you make any significant change to your device you risk problems.

Step1: Connect your iDevice to PC using the USB cable and launch 3uTools on your PC. 

Step 2: Click "Flash & JB" -> "Easy Flash", then select the firmware iOS 11.2.5 beta4, finally click "Flash". (If you want to save iDevice's data, you need to select the checkbox that "Retain User's Data While Flashing")

You’ll get a reminder that “Retain User’s Data While Flashing” can’t always keep your data while flashing, and some or all data might get lost after flashing. Sure you want to select the checkbox? Click OK.

Step3: Keep a good connection between iDevice and PC, and then just wait patiently till this process is finished. The whole flashing process needs 5~10 minutes in general, when it's finished, then you can experience iOS 11.2.5 beta 4 freely.