No, I don't know of any applications that do that.
I have detailed billing on Rogers, and that pretty much gives me everything I need to know (caller number, duration, date, time, incoming/outgoing, etc.). I suppose if one wanted to compare the total time, then on billing start day (mine is the 11th of each month), I could look at and make note of the Phone Info (green call button, Status) where it gives your total Call Time. Compare that time with the same info a month from now and the difference would be the total call time for the month (you could set up a calendar reminder to check the Status at the beginning of your call cycle).
Other than that, I can't think of anything that would help you.
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