RacquetTune measures frequency and uses that frequency to calculate tension using a string factor that may or may not be accurate. That string factor often changes for different types of string, even string gauge or dyes in the string can change the string factor. The best you can hope for is the measured tension of the string in the racket might be close. I have my doubts. I seriously doubt all the mains are the same tension let alone all the mains and crosses are the same tension. Try using a string meter and you probably won’t find any main and cross the same.
I’d measure frequency and forget about tension, dynamic tension, string gauge, string color, string savers, head size, pattern, string factors, and anything else that can change the reading. That is if I wanted to measure whatever it is anyway. It is what it is.