Re:Thermometer for iPhone?

Sorry about the earlier post. As I am bilingual, sometimes I forget the right language to use. So here is the English version:
I often missed the ability to measure the temperature near me with my mobile phone. Accuweather and other apps are not good for this. Obviously, a built-in chip wouldn't be good either, because it would take the temperature of the heated iPhone. I was thinking of some external gadget that could be plugged into the USB-C port with an app written for it that would show the temperature. I don't want to carry around a manual thermometer.