Check-in from Dashboard
I'm not using any external app.
So I basically use Trakt on Web brower on my PC or phone for my checkins.
I would find it useful being able to check-in right away from the dashboard (Up next to watch section) without having to access the episode in the first place.
itachi shared this idea
I'm not sure if the collect buttons are that useful on the Up Next to watch section.
So maybe you could replace them with the check-in button