Using “for” or “in” with perfect tenses

Question

I am not sure about the difference between "for" and "in" with perfect tenses. Is there a difference in meaning?

1- She hasn't taken her eyes off her phone in two hours.

2- She hasn't taken her eyes off her phone for two hours.

3- We haven't talked in 10 years.

4- We haven't talked for 10 years.

Answer 1

In this context, there's no difference in meaning.

"In" suggests within some given time period, while "for" suggests some given duration of time ... but this is, as we say, "six of one, half-dozen of the other", meaning it's two different ways of saying the same thing.