While this is nice, it results in a big static lib(27M) to include in your app. This might be okey for some games, but maybe not for small apps. I was very interested in a Haskell app, but eventually gave up because of this...
the twitter app is 30M, we have already past the point of sensible app sizes.
edit: fb messenger is 60M, a ghc-ios app with the elm compiler baked in is 24M.