This is how it works:
There are no rounded-in-F temps. Note: if you are using the Chart Neo app without Tempdrop, then always enter the raw F temp and not a rounded F temp.
The temp display can show Celsius numbers or Fahrenheit numbers, but it is the exact same rounded-in-C temp.
No, we recommend you continue to chart in your native temp scale. In Fahrenheit you use the number displayed as a range check, such as too high means possible fever and too low means too loose armband. This is most intuitively done in your native temp scale. So, the Fahrenheit number display is still useful even if you do not use the number to self-interpret your chart.
You do this by looking at the dot pattern or deviation pattern. The horizontal lines shown on the Chart Neo app chart are separated by 0.05ºC, which equals approximately 0.1ºF. This is 1 deviation or 1D. When you are looking for a temp to be 0.2ºC (approximately 0.4ºF) above the coverline, you are looking for a temp that is 4 deviations (4D) above the coverline. That means you count 4 lines above the coverline and look at that point or above to find it. This way of chart reading works for any chart displayed with a proper horizontal grid behind it, like most paper charts.