Best app or fake like others

HI WHO HAVE BEEN USING <a href="https://play.google.com/store/apps/details?id=com.glow.android">GLOW APP</a> FOR THERE FERTILE N PERIOD DAYS HAS IT BEEN ON POINT EVERY MONTH ON YOUR DAYS CUZ SOME OF THIS APPS BE CONFUSE WITH OUR PERIODS.OVALATING. FERTILE ETC UGH ? I HATE TO BE LOST OR CONFUSE