ASP.NET Identity Remember Me

I have built an application targeted at mobile devices. I would like to be able to check the "remember me" option when logging in, and then be automatically authenticated from that point on, whenever I visit the site (app) or click on a link in an SMS that directs my browser to an authenticated controller action.
Unfortunately, it seems that I must have something incorrectly set somewhere, as I am required to login almost every time I visit the site, even though I have selected "remember me".
In my Startup.Auth.cs file, I have the following in ConfigureAuth:
           
app.CreatePerOwinContext(ApplicationDbContext.Create); app.CreatePerOwinContext<ApplicationUserManager>(ApplicationUserManager.Create); app.CreatePerOwinContext<ApplicationRoleManager>(ApplicationRoleManager.Create); ...