Trakt for iOS
Works on iPhone and iPad.
http://josswhedon.blogspot.com/2012/04/buffy-and-angel-episode-viewing-order.html?m=1
http://buffy.wikia.com/wiki/Viewing_order_suggestion_for_Buffy_and_Angel
The optimal viewing order for episode of Buffy the Vampire Slayer and Angel, to keep the shows in chronological order as they crossover
http://slayalive.com/showthread.php/3924-The-Buffy-Angel-watching-guide
watched in 2021
Correct order for viewing Buffy the Vampire Slayer & Angel
Buffyverse
by Yasve