This is such awesome news!!! It was the sole reason I last jailbroke my phone.

They're even letting people install it from source so you get it before it gets on the app store: https://justgetflux.com/sideload/

It won't get on the app store, it uses a private API.

f.lux is awesome, wasn't even aware it was available for phones. Apparently it's not on android but there's Twilight for android which does the same thing and I just tested it out and it's pretty good!