From their FAQ: * Google Chrome: version 4.249.4+ * Mozilla Firefox: version: 3.5+ * Apple Safari: version 3.1+ * Opera: versio

From their FAQ: * Google Chrome: version 4.249.4+ * Mozilla Firefox: version: 3.5+ * Apple Safari: version 3.1+ * Opera: version 10.5+ * Microsoft Internet Explorer: version 6+ The Google Font API is not currently supported on iPhone, iPad, iPod, or Android