This app was mentioned in 1 comment, with an average of 4.00 upvotes
You just inspired me to write an android version! You can find the source here: https://github.com/jayseejc/XKCD-Dating-Age-Calculator
I'll attach the play store link in the morning when it goes live.
UPDATE: Play store link https://play.google.com/store/apps/details?id=com.jayseeofficial.agecalculator