As you might be aware, National Geographic’s Park Guides is a beautiful app, that uses some nice CoreAnimation techniques to create some cool effects.
You start by clicking on the Weather icon, or the one bellow:
And here the final position:
You can also find this kind of stuff in WeatherNeue, but I must confess that in the first it looks better. If you wonder how you can use these animations, you can check this library, done by Kent Nguyen. Great stuff indeed.