Fertility days and ovulation tests

Ashley
Hey Glow, I am currently on my 3rd fertile day (15% fertile according to Glow). I started to take Clearblue ovulation tests yesterday, even though yesterday was my 11% fertile day. Yesterday and today have both given the same test results: not fertile. 
My question is, how accurate has your <a href="https://play.google.com/store/apps/details?id=com.glow.android">fertility tracker</a> been when testing with ovulation kits? Also, did you not see the high fertility results until the 27% or 33% fertile days? 
Thanks in advance 💜