Trakt for iOS
Works on iPhone and iPad.
Vikings started off as such a strong show but this season was awful. I couldn't even finish it. At this rate they should just end this show.
season 4 was split. With the first 6 episodes coming out in 2018 and the rest of the season in 2019
Season 2 lost some of the momentum that made season 1 good.
The Christmas special/ New Years special for this season is called resolution. It is also worth a watch.