BJCP 2015 presents the information from the BJCPs 2015 Beer, Mead, and Cider Style Guidelines as genuinely as possible. The introductory sections have been moved out of the main flow of the app as you would see them in a hardbound edition of the Guidelines; this was done strictly from a usability standpoint for anyone using this app while judging a competition. That said, the entirety of the 2015 Style Guidelines are included in BJCP 2015. More importantly, the Guidelines are presented with their intention intact. To put it precisely, if there is a word italicized or bolded for emphasis in the official Guidelines youll find that the same emphasis is placed in the text herein.
If you are looking for crossover between the 2008 guidelines and the 2015 guidelines be sure to check out Appendix: A in the Intros & Appendices section. The authors have done a fantastic job of cross-referencing the styles in multiple manners beyond just a comparison of these guidelines and the previous version.