For the first time, Apple is making developer previews for iOS and other beta versions available for free download to anyone who registers as a developer.
Previously, these early versions were only accessible to those who paid $99 per year for a developer account. However, one still needs to register as a developer to gain access to the betas. This can be done for free with an Apple ID and provides access to Xcode, downloads of other software, documentation, code samples, forums, and the Feedback Assistant.
However, an Apple Developer Program account is still required for app distribution.