As I haven't found a single thermometer that lives up to my requirements so far, I decided to go for it and pre-order the crowdfunded Tempdrop! I like that it monitors your temperature throughout the night to find your right basal body temperature. Also, it's great not having to set the alarm to chart manually with a thermometer at the same time every morning (which I do for my fertility cycle tracking). Check out the pics below to find out how it works and the difference to a regular BBT thermometer.
Keep an eye out for my review!
More info here: https://tempdrop.xyz/products/tempdrop