iOS 12.4.6 is available over-the-air in the Settings app. Just make sure that your iPhone is connected to a Wi-Fi hotspot and browse for General -> Software Update. Tap on Download and Install. Provide the Passcode, confirm that you want to upgrade and wait until the new version is downloaded and unpacked on your device. The iPhone will automatically reboot when ready.
iOS 12.4.6 Update Log
In the Software Update screen Apple informs that his new version “provides important security improvements and is recommended for all users.”
There is no other extended update log or no other mentions, meaning that no new features have been added besides improved security.
Size: You can tell that the update is a minor one from the size of the file. Under 60 MB.
The security content of this update is available at: https://support.apple.com/kh/HT20122
Devices That Qualify For iOS 12.4.6 Update
iPhone: iPhone 5s, iPhone 6 and iPhone 6 Plus.
iPad: iPad Air (1st generation), iPad mini 2 and iPad mini 3.
iPod: iPod touch (6th generation).
Do you still daily use an iPhone 6 or older version? Let us know in the comment section available below!