Apple - iOS 12.3
|Software Version:||iOS 12.3|
iOS 12.3 includes support for AirPlay 2 enabled TVs and features a redesigned Apple TV app. This update also includes bug fixes and improvements.
For information on the security content of Apple software updates, please visit this website: https://support.apple.com/kb/HT201222
Yes, iPhones get their updates from Apple servers. You can update it simply while on Wifi, no phone activation.
I am about to purchase and iphone 8 from boost but need it to be on iOS 12. Is this update available immediately upon activation of an iphone 8?