What’s better

Is this app better and more accurate or is the Premom app? I have both. This app says I ovulate in 16 days. The premom app says I ovulate in 6 days. I don’t know what one is better. And more accurate my period was 2 days, on the 28 and 29th this month. I don’t have opk’s right now.. so I can’t detect when i actually peak which is why I need help with what app is better and more accurate. What was your experience with each?