iOS15.4 Updates
Finally the 15.4 brings the Face Unlock feature with a mask. Until this update, the iPhone users were able to unlock their iPhone using 6 digit secure code or thumb impression. However, the iPhone models that came up with face unlock had only one option, which is using the secure code. So this new update puts an end to that hassle.
Face Id with a Mask
Some of the Latest iPhone models got some New Live wallpapers after this update. Go to Settings : Wallpaper

New iPhone Wallpapers
Now we can Download iOS updates using Cellular Data. The ios update requires Wi-Fi connectivity to download OS updates. But, Now we can use Cellular Data to download the Latest OS updates.

iOS 15.4
30+ New Emojis

ios 15.4 New Emojis
Hey Siri got a NEW VOICE

Hey Siri New Voice
“Notes” Field added in Passwords. Now you can add notes to the stored passwords in the iPhone.

Notes in Password
iOS15.4 Updates
If i missed any important features or updates, please share the same in the comment section. So we all could benefit from it.
Checkout the ios 15 update features in the following link.
iOS15 is here : The Best New features of Apple’s iOS 15 you want to know