Great idea but not practical

I really love the idea of this app. Unfortunately it does not work as supposed. I use it together with my Philips Hue-System.
Pairing works flawlessly and if you open the app it indeed sets the color-temperature of your bulbs according to the local sun position.
BUT the Background-Sync Option has no effect, so the lights are not updated when you dont leave the app open and active.
Without this functionality, in my opinion the core feature of such an app, this app is nearly useless.
Id love to see an update on that.

art.vandalay about Sunn - Circadian Lighting for Philips Hue, v1.11