Why hasn't Google updated Android apps to match iOS?

The iOS versions of Maps, Gmail (and probably something else I'm forgetting) are now much better than the Android equivalents, ever since Google was forced to provide native apps. I'm guessing these apps were written from scratch and thus have a totally new UI, while the Android apps are full of legacy code which may make it harder to update them. None of that matters though. For a company with the engineering resources of Google, this shouldn't happen! Android is their baby, and things like this just perpetuate the impression that iOS has better apps. I mean, how hard can it be?