After the design and construction phase, an application or a new operating system goes through several stages until it is installed on all users' devices.
Regarding watchOS, iOS, iPadOS, tvOS and macOS operating systems, two of these stages are:
1. Apple Developer Program (Developer Beta), where application developers can create, optimize and test applications for the future operating system.
2. Apple Beta Software Program (Public Beta), where all users who want to test and discover the new features of the future operating system can register.
The future iOS 15 / iPadOS 15 was presented on June 7 in the WWDC21, and immediately after the end of the event, the first beta version was made available to the developers.

When will iOS 15 and iPadOS 15 Public Beta be released?
The release date of the first Public Beta version for iOS 15 and iPadOS 15 has not been announced by Apple yet, but it will most likely happen on towards the end of June, if we are to take the release dates of the previous beta versions of iOS 14 and iOS 13.
The first version Public Beta a iOS 14 was officially launched on July 9, 2020, after it was first presented at WWDC20, during the period June 22-26. The event was usually held in June, but the pandemic forced Apple to postpone it and hold it under special conditions.
iOS 13 Public Beta was launched on June 24, 2019, again iOS 12 Public Beta on June 25.
If we are to make a pertinent estimate based on the previous data, there are good chances that iOS 15 Public Beta to be released towards the end of June 2021 or the late one at the beginning of July.








