How does glow predict ovulation?

This is my first cycle but I've been chatting for months (in other apps) and am pretty good at it. Glow tells me this month i ovulated 3d after my temp shift/peak day, which seems wrong. And while I'm at it- how does it determine the chance of pregnancy? As a "test" I told it I had sex 3x during my fertile window, and it says my chance of pregnancy is 1%. And finally- it asks what position you had sex in and if you had an orgasm, but it DOESN'T ask if it was protected or not!! That's a million times more important to you chances of conception than position and orgasm (which are pretty UNimportant)