Ok, so looks like the feature doesn't work in the default Android browser in Android. It does work in Chrome and Firefox for Android. Apparently it doesn't work in Chrome for iOS either...
I'm kinda torn. Internet for Android makes up less than 1% of my hits, and with two compatible free browsers available and being the only developer, I'm not sure dedicating the time to QA on a browser known for not processing CSS well is worthwhile.
However, the bug that's making it not work on iOS may be the same issue with Internet for Android.