Different Apps, Different results

Jane • 👼🏻 9/9/2019 👼🏻 4/20/2020

So I have put my cycle info into three apps. Usually I just go off of glow but I’ve I been through 5 months of TTC after MMC with no luck, so I decide to try a few different apps. These apps all three show that my Ovulation day was different. My opk test showed positive (I think) on the 8th. Anyone have any suggestions for the most accuracy/best chances?