[header] How to manage your watchlist on imdb [title] Open the imdb mobile app. [step] Make sure to login with the same account you'd use on a desktop pc. If you have an amazon, google or facebook account, you can create one single account easily, or you can use an imdb account. 
[title] Find movies or shows you want to add to your watchlist. [step] You can use the search box at the top of the page, or you can browse the page of current movie pages.