How do you go to the previous route in iron-router?

I'm using an event handler to go to the previous URL/route:

'click #back': ->
  history.back()

This works in Chrome desktop, Chrome devtools mobile device view, and in Safari on a physical device itself (iOS 8.1.2), but not in Chrome on the device. Behavior is:

• Load /
• Click link to /foo
• URL changes to /foo, and foo template renders
• Click #back
• URL changes to / briefly, then changes back to /foo. The page body does not change. (Correct behavior is the URL permanently changes to /, and the / templates are rendered, without a page load.)
• Click #back second time
• / is reloaded from server

Is this a mobile Chrome problem, or should I be using some iron-router API like Router.back()?

history.back() is the method supported by iron-router, it just appears there's a problem with iOS Chrome.