All android and iOS apps can see your VPN

I didn’t think the ability to detect the presence of a VPN tunnel is a problem. The fact that some apps stop doing what they should do when they detect a VPN tunnel is worrying though. Perhaps ideally apps should not know whether a VPN is active or not and be agnostic about how its own traffic is routed. Apps that enumerate all installed apps are a big problem. Some ways to mitigate this may be use only FOSS apps or add some sort of sandboxing.