Which app is correct?

Question

I've been using glow and my days for months. My days longer. My days says 7 days til af and glow says 4 days. Which is it do you think?

Answer

I also use my days and its ways been spot on, yet glow is telling me otherwise. With mydays I was fertile from the 10th until the 15th I think, where as glow says 14th to the 19th. Yet I have fertile CM from the 10th to 15th x

Which app is correct?

Let's Glow!

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