I would like a Generic Fader to be used in Dashboard.
It could be used for audio, opening curtains or windscreens.
There are so much devices to be controlled with a 0 - 100% action.
This shouldnt be that hard to create? Or can somebody make an app for it?
Sadly, it’s out of my technical reach to do it myself.
Have you looked at the Enhanced Device widget?
You can add a widget for any device and select which of it’s capabilities to view. That includes a slider for curtains.
Generic faders need to be able to control all your devices, otherwise they’re not generic 
Homey doesn’t provide fine-grained access control for apps, it’s either “app-devices only” or “all devices”, there’s nothing in between.
Thank you for clarifying it.
I was more afraid for retreiving user data, network information or changing settings. Not for the controlling for devices itself.
Like I said, Homey doesn’t provide fine-grained access control.
