My cycle-tracking apps aren't aligned, which should I trust ?

Nat

I'd only started tracking my periods late last year with the apple health app, and then with <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">eve</a> and another app called cycles. With apple and cycles i track factors like symptoms/ pills taken/ sex.

Apple's app can't predict ovulation/ fertility. Both apple and cycles' predicted cycles don't line up. With <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">eve</a>, it's slightly more aligned with apple's but is completely different than cycles'.

I want to plan around my cycle but i'm unsure of which app is accurate. I can't predict cycle phases as i've always had an irregular one. Which app should i trust ? Is there any other way to track a cycle ?

If anyone has any tips then please let me know !! Thank you so much xx