What do you think of ovulation tracker apps

I used Flo and got pregnant my first try however I had a miscarriage! As I look deeper on to this I realised I was just lucky as apps are just an estimation! For best result I now also use Fertility Friend (FF) as I temp now. I’m also using clearblue ovulation stick to identify the “peak” date of the cycle.

I using Flo. And it did track my ovulation quite accurately