Yes, I've used and heard this Down Under. We often add "mate" to the end, and even shorten it: "She's apps, mate." (Long before phone app technology existed.)
It's a reassurance that everything will turn out OK, or that everything is fine and under control. Apparently it comes from our rhyming slang, "apples and spice" = "nice", but I'm not sure how true that is. This is a fairly old expression, in Australian years.