Apple released the first iOS version 12 for public testing. Functionally it corresponds to the 12 iOS Developer Beta 2, released last week.
iOS 12 2018 presented at WWDC in early June. The system has become faster, expanded platform capabilities ARKit, revised several system apps, and Siri has got a new function. A full release of the OS will happen in the fall.
Check in the beta program Apple takes place on a special web site. A public beta of iOS 12 are available for iPhone 5S and newer, iPad mini 2 and later and iPod Touch 6. Before you install the preview it is advisable to make a backup of your device.