Ovulation app

Hi ladies, I'm new here. My name is Melissa, 30 years old, and we're hoping for a second baby.

I'm wondering if you have an app that shows you when your ovulation is? I only have the Calendar app, but it says I'll ovulate on Christmas. I've entered my details on 4 other apps, and they all say ovulation is on the 29th. So I'm wondering if you have a good app or how you track it.

Thanks!