Cubic Theme Infinite Scrolling on Mobile

Infinite scrolling works great with Cubic on Mac and iPad, but I only get 7 posts when I generate a return from a category (example on iPhone here: issuesindigitalhistory.net, which forwards to http://www.michaeljkramer.net/cr/category/issues-in-digital-history). Looks lovely with infinite scrolling on desktop or iPad, but seems to not do infinite scrolling on an iPhone or mobile device.

I wonder if this is because there is a footer at the bottom for the Cubic theme, but not sure. Have checked all settings and tried using Mobile Smart plug in.

Any other hunches how to get infinite scrolling to work with Cubic from a category?

Thanks!
Michael