What about below freezing temperatures? – Unit Converter - Best Unit App Review

I have been using Units Plus for years as the easiest converter app for most measurements — weight, currency, length, etc. Now that it’s winter, however, I find it very frustrating to have to switch to a different app to convert below freezing temperatures from Celsius to Fahrenheit. The +/- symbols don’t work.
Review by Mac since 512k on Unit Converter - Best Unit App.