TWW 5dpo temperature check question

I’ve been using the temple thermometer to check my temp throughout the day and log it in my apps. Today my temple therm. Came up 100.7, then 100.0, lastly this evening 99.5

I also use my “under the tongue” therm. Which has been chilling around 98.5/98.7

I researched on google and it says temple therm. Is .5/1. Lower than your temp to add, and others says reduce to amount by .5/1. Degrees.

I’m not sure how to log my temp. In these apps/which one I should go off of?

How do you ladies take your temp and is the most accurate 🙂

Thanks