The new iOS 13 will be the most demanding of resources, so many old devices will not work. ( iOS 13 supported devices )
iOS 13 will be presented in June 2019 at the WWDC 2019 conference, it's mean that new iOS 13 release date - 3-th, June, 2019.
Don't forget read more about dark mode in iOS 13
Apple will, for the first time after iOS 7, rework the home screen in iOS 13. The design of the home screen of the operating system has hardly changed since the very first version of iOS, but Apple managed to figure out how to update it in the most appropriate way. There are no details on how the iOS 13 main screen will look.
iOS 13 Release Date, Rumors and Updates:
A source only stressed that the update will greatly increase the productivity of users of the iPhone and iPad. It is also known that iOS 13 is developed under the code name "Yukon". Information about the firmware is kept in the strictest confidence. Apple does not want the details of the upcoming large-scale update to be made publicly ahead of time.